804 lines
27 KiB
C++
804 lines
27 KiB
C++
/*
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* Copyright (C) 2016 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#define LOG_TAG "keystore"
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#include "keystore.h"
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#include <dirent.h>
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#include <fcntl.h>
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#include <openssl/bio.h>
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#include <utils/String16.h>
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#include <utils/String8.h>
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#include <keystore/IKeystoreService.h>
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#include <android/hardware/keymaster/3.0/IKeymasterDevice.h>
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#include "keystore_utils.h"
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#include "permissions.h"
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#include <keystore/keystore_hidl_support.h>
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const char* KeyStore::sOldMasterKey = ".masterkey";
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const char* KeyStore::sMetaDataFile = ".metadata";
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const android::String16 KeyStore::sRSAKeyType("RSA");
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using namespace keystore;
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using android::String8;
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KeyStore::KeyStore(Entropy* entropy, const km_device_t& device, const km_device_t& fallback,
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bool allowNewFallback)
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: mEntropy(entropy), mDevice(device), mFallbackDevice(fallback),
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mAllowNewFallback(allowNewFallback) {
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memset(&mMetaData, '\0', sizeof(mMetaData));
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}
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KeyStore::~KeyStore() {
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for (android::Vector<UserState*>::iterator it(mMasterKeys.begin()); it != mMasterKeys.end();
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it++) {
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delete *it;
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}
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mMasterKeys.clear();
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}
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ResponseCode KeyStore::initialize() {
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readMetaData();
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if (upgradeKeystore()) {
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writeMetaData();
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}
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return ResponseCode::NO_ERROR;
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}
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ResponseCode KeyStore::initializeUser(const android::String8& pw, uid_t userId) {
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UserState* userState = getUserState(userId);
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return userState->initialize(pw, mEntropy);
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}
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ResponseCode KeyStore::copyMasterKey(uid_t srcUser, uid_t dstUser) {
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UserState* userState = getUserState(dstUser);
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UserState* initState = getUserState(srcUser);
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return userState->copyMasterKey(initState);
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}
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ResponseCode KeyStore::writeMasterKey(const android::String8& pw, uid_t userId) {
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UserState* userState = getUserState(userId);
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return userState->writeMasterKey(pw, mEntropy);
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}
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ResponseCode KeyStore::readMasterKey(const android::String8& pw, uid_t userId) {
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UserState* userState = getUserState(userId);
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return userState->readMasterKey(pw, mEntropy);
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}
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/* Here is the encoding of keys. This is necessary in order to allow arbitrary
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* characters in keys. Characters in [0-~] are not encoded. Others are encoded
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* into two bytes. The first byte is one of [+-.] which represents the first
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* two bits of the character. The second byte encodes the rest of the bits into
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* [0-o]. Therefore in the worst case the length of a key gets doubled. Note
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* that Base64 cannot be used here due to the need of prefix match on keys. */
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static size_t encode_key_length(const android::String8& keyName) {
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const uint8_t* in = reinterpret_cast<const uint8_t*>(keyName.string());
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size_t length = keyName.length();
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for (int i = length; i > 0; --i, ++in) {
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if (*in < '0' || *in > '~') {
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++length;
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}
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}
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return length;
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}
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static int encode_key(char* out, const android::String8& keyName) {
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const uint8_t* in = reinterpret_cast<const uint8_t*>(keyName.string());
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size_t length = keyName.length();
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for (int i = length; i > 0; --i, ++in, ++out) {
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if (*in < '0' || *in > '~') {
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*out = '+' + (*in >> 6);
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*++out = '0' + (*in & 0x3F);
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++length;
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} else {
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*out = *in;
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}
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}
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*out = '\0';
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return length;
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}
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android::String8 KeyStore::getKeyName(const android::String8& keyName, const BlobType type) {
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std::vector<char> encoded(encode_key_length(keyName) + 1); // add 1 for null char
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encode_key(encoded.data(), keyName);
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if (type == TYPE_KEY_CHARACTERISTICS) {
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return android::String8::format(".chr_%s", encoded.data());
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} else {
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return android::String8(encoded.data());
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}
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}
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android::String8 KeyStore::getKeyNameForUid(
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const android::String8& keyName, uid_t uid, const BlobType type) {
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std::vector<char> encoded(encode_key_length(keyName) + 1); // add 1 for null char
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encode_key(encoded.data(), keyName);
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if (type == TYPE_KEY_CHARACTERISTICS) {
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return android::String8::format(".%u_chr_%s", uid, encoded.data());
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} else {
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return android::String8::format("%u_%s", uid, encoded.data());
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}
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}
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android::String8 KeyStore::getKeyNameForUidWithDir(
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const android::String8& keyName, uid_t uid, const BlobType type) {
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std::vector<char> encoded(encode_key_length(keyName) + 1); // add 1 for null char
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encode_key(encoded.data(), keyName);
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if (type == TYPE_KEY_CHARACTERISTICS) {
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return android::String8::format("%s/.%u_chr_%s", getUserStateByUid(uid)->getUserDirName(),
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uid, encoded.data());
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} else {
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return android::String8::format("%s/%u_%s", getUserStateByUid(uid)->getUserDirName(), uid,
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encoded.data());
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}
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}
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NullOr<android::String8> KeyStore::getBlobFileNameIfExists(const android::String8& alias, uid_t uid,
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const BlobType type) {
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android::String8 filepath8(getKeyNameForUidWithDir(alias, uid, type));
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if (!access(filepath8.string(), R_OK | W_OK)) return filepath8;
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// If this is one of the legacy UID->UID mappings, use it.
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uid_t euid = get_keystore_euid(uid);
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if (euid != uid) {
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filepath8 = getKeyNameForUidWithDir(alias, euid, type);
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if (!access(filepath8.string(), R_OK | W_OK)) return filepath8;
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}
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// They might be using a granted key.
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auto grant = mGrants.get(uid, alias.string());
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if (grant) {
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filepath8 = String8::format("%s/%s", grant->owner_dir_name_.c_str(),
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getKeyNameForUid(String8(grant->alias_.c_str()), grant->owner_uid_, type).c_str());
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if (!access(filepath8.string(), R_OK | W_OK)) return filepath8;
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}
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return {};
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}
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void KeyStore::resetUser(uid_t userId, bool keepUnenryptedEntries) {
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android::String8 prefix("");
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android::Vector<android::String16> aliases;
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UserState* userState = getUserState(userId);
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if (list(prefix, &aliases, userId) != ResponseCode::NO_ERROR) {
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return;
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}
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for (uint32_t i = 0; i < aliases.size(); i++) {
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android::String8 filename(aliases[i]);
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filename = android::String8::format("%s/%s", userState->getUserDirName(),
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getKeyName(filename, TYPE_ANY).string());
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bool shouldDelete = true;
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if (keepUnenryptedEntries) {
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Blob blob;
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ResponseCode rc = get(filename, &blob, ::TYPE_ANY, userId);
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switch (rc) {
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case ResponseCode::SYSTEM_ERROR:
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case ResponseCode::VALUE_CORRUPTED:
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// If we can't read blobs, delete them.
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shouldDelete = true;
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break;
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case ResponseCode::NO_ERROR:
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case ResponseCode::LOCKED:
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// Delete encrypted blobs but keep unencrypted blobs and super-encrypted blobs. We
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// need to keep super-encrypted blobs so we can report that the user is
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// unauthenticated if a caller tries to use them, rather than reporting that they
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// don't exist.
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shouldDelete = blob.isEncrypted();
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break;
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default:
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ALOGE("Got unexpected return code %d from KeyStore::get()", rc);
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// This shouldn't happen. To be on the safe side, delete it.
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shouldDelete = true;
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break;
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}
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}
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if (shouldDelete) {
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del(filename, ::TYPE_ANY, userId);
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// del() will fail silently if no cached characteristics are present for this alias.
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android::String8 chr_filename(aliases[i]);
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chr_filename = android::String8::format("%s/%s", userState->getUserDirName(),
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getKeyName(chr_filename,
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TYPE_KEY_CHARACTERISTICS).string());
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del(chr_filename, ::TYPE_KEY_CHARACTERISTICS, userId);
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}
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}
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if (!userState->deleteMasterKey()) {
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ALOGE("Failed to delete user %d's master key", userId);
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}
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if (!keepUnenryptedEntries) {
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if (!userState->reset()) {
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ALOGE("Failed to remove user %d's directory", userId);
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}
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}
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}
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bool KeyStore::isEmpty(uid_t userId) const {
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const UserState* userState = getUserState(userId);
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if (userState == NULL) {
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return true;
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}
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DIR* dir = opendir(userState->getUserDirName());
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if (!dir) {
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return true;
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}
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bool result = true;
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struct dirent* file;
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while ((file = readdir(dir)) != NULL) {
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// We only care about files.
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if (file->d_type != DT_REG) {
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continue;
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}
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// Skip anything that starts with a "."
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if (file->d_name[0] == '.') {
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continue;
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}
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result = false;
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break;
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}
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closedir(dir);
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return result;
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}
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void KeyStore::lock(uid_t userId) {
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UserState* userState = getUserState(userId);
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userState->zeroizeMasterKeysInMemory();
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userState->setState(STATE_LOCKED);
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}
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ResponseCode KeyStore::get(const char* filename, Blob* keyBlob, const BlobType type, uid_t userId) {
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UserState* userState = getUserState(userId);
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ResponseCode rc =
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keyBlob->readBlob(filename, userState->getEncryptionKey(), userState->getState());
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if (rc != ResponseCode::NO_ERROR) {
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return rc;
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}
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const uint8_t version = keyBlob->getVersion();
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if (version < CURRENT_BLOB_VERSION) {
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/* If we upgrade the key, we need to write it to disk again. Then
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* it must be read it again since the blob is encrypted each time
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* it's written.
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*/
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if (upgradeBlob(filename, keyBlob, version, type, userId)) {
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if ((rc = this->put(filename, keyBlob, userId)) != ResponseCode::NO_ERROR ||
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(rc = keyBlob->readBlob(filename, userState->getEncryptionKey(),
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userState->getState())) != ResponseCode::NO_ERROR) {
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return rc;
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}
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}
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}
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/*
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* This will upgrade software-backed keys to hardware-backed keys.
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*/
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if (rc == ResponseCode::NO_ERROR && type == TYPE_KEY_PAIR && keyBlob->isFallback()) {
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ResponseCode imported =
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importKey(keyBlob->getValue(), keyBlob->getLength(), filename, userId,
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keyBlob->isEncrypted() ? KEYSTORE_FLAG_ENCRYPTED : KEYSTORE_FLAG_NONE);
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// The HAL allowed the import, reget the key to have the "fresh" version.
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if (imported == ResponseCode::NO_ERROR) {
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rc = get(filename, keyBlob, TYPE_KEY_PAIR, userId);
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}
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}
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// Keymaster 0.3 keys are valid keymaster 1.0 keys, so silently upgrade.
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if (keyBlob->getType() == TYPE_KEY_PAIR) {
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keyBlob->setType(TYPE_KEYMASTER_10);
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rc = this->put(filename, keyBlob, userId);
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}
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if (type != TYPE_ANY && keyBlob->getType() != type) {
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ALOGW("key found but type doesn't match: %d vs %d", keyBlob->getType(), type);
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return ResponseCode::KEY_NOT_FOUND;
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}
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return rc;
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}
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ResponseCode KeyStore::put(const char* filename, Blob* keyBlob, uid_t userId) {
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UserState* userState = getUserState(userId);
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return keyBlob->writeBlob(filename, userState->getEncryptionKey(), userState->getState(),
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mEntropy);
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}
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static NullOr<std::tuple<uid_t, std::string>> filename2UidAlias(const std::string& filename);
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ResponseCode KeyStore::del(const char* filename, const BlobType type, uid_t userId) {
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Blob keyBlob;
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auto uidAlias = filename2UidAlias(filename);
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uid_t uid;
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std::string alias;
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if (uidAlias.isOk()) {
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std::tie(uid, alias) = std::move(uidAlias).value();
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}
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ResponseCode rc = get(filename, &keyBlob, type, userId);
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if (rc == ResponseCode::VALUE_CORRUPTED) {
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// The file is corrupt, the best we can do is rm it.
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if (uidAlias.isOk()) {
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// remove possible grants
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mGrants.removeAllGrantsToKey(uid, alias);
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}
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return (unlink(filename) && errno != ENOENT) ?
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ResponseCode::SYSTEM_ERROR : ResponseCode::NO_ERROR;
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}
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if (rc != ResponseCode::NO_ERROR) {
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return rc;
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}
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auto& dev = getDevice(keyBlob);
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if (keyBlob.getType() == ::TYPE_KEY_PAIR || keyBlob.getType() == ::TYPE_KEYMASTER_10) {
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auto ret = KS_HANDLE_HIDL_ERROR(dev->deleteKey(blob2hidlVec(keyBlob)));
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// A device doesn't have to implement delete_key.
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if (ret != ErrorCode::OK && ret != ErrorCode::UNIMPLEMENTED)
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return ResponseCode::SYSTEM_ERROR;
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}
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rc = (unlink(filename) && errno != ENOENT) ?
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ResponseCode::SYSTEM_ERROR : ResponseCode::NO_ERROR;
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if (rc == ResponseCode::NO_ERROR && keyBlob.getType() != ::TYPE_KEY_CHARACTERISTICS) {
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// now that we have successfully deleted a key, let's make sure there are no stale grants
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if (uidAlias.isOk()) {
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mGrants.removeAllGrantsToKey(uid, alias);
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}
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}
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return rc;
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}
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/*
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* Converts from the "escaped" format on disk to actual name.
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* This will be smaller than the input string.
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*
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* Characters that should combine with the next at the end will be truncated.
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*/
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static size_t decode_key_length(const char* in, size_t length) {
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size_t outLength = 0;
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for (const char* end = in + length; in < end; in++) {
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/* This combines with the next character. */
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if (*in < '0' || *in > '~') {
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continue;
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}
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outLength++;
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}
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return outLength;
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}
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static void decode_key(char* out, const char* in, size_t length) {
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for (const char* end = in + length; in < end; in++) {
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if (*in < '0' || *in > '~') {
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/* Truncate combining characters at the end. */
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if (in + 1 >= end) {
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break;
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}
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*out = (*in++ - '+') << 6;
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*out++ |= (*in - '0') & 0x3F;
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} else {
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*out++ = *in;
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}
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}
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*out = '\0';
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}
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static NullOr<std::tuple<uid_t, std::string>> filename2UidAlias(const std::string& filepath) {
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auto filenamebase = filepath.find_last_of('/');
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std::string filename = filenamebase == std::string::npos ? filepath :
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filepath.substr(filenamebase + 1);
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if (filename[0] == '.') return {};
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auto sep = filename.find('_');
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if (sep == std::string::npos) return {};
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std::stringstream s(filename.substr(0, sep));
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uid_t uid;
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s >> uid;
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if (!s) return {};
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auto alias = filename.substr(sep + 1);
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std::vector<char> alias_buffer(decode_key_length(alias.c_str(), alias.size()) + 1);
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decode_key(alias_buffer.data(), alias.c_str(), alias.size());
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return std::tuple<uid_t, std::string>(uid, alias_buffer.data());
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}
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ResponseCode KeyStore::list(const android::String8& prefix,
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android::Vector<android::String16>* matches, uid_t userId) {
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UserState* userState = getUserState(userId);
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size_t n = prefix.length();
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DIR* dir = opendir(userState->getUserDirName());
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if (!dir) {
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ALOGW("can't open directory for user: %s", strerror(errno));
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return ResponseCode::SYSTEM_ERROR;
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}
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struct dirent* file;
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while ((file = readdir(dir)) != NULL) {
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// We only care about files.
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if (file->d_type != DT_REG) {
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continue;
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}
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// Skip anything that starts with a "."
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if (file->d_name[0] == '.') {
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continue;
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}
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if (!strncmp(prefix.string(), file->d_name, n)) {
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const char* p = &file->d_name[n];
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size_t plen = strlen(p);
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size_t extra = decode_key_length(p, plen);
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char* match = (char*)malloc(extra + 1);
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if (match != NULL) {
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decode_key(match, p, plen);
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matches->push(android::String16(match, extra));
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free(match);
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} else {
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ALOGW("could not allocate match of size %zd", extra);
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}
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}
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}
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closedir(dir);
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return ResponseCode::NO_ERROR;
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}
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std::string KeyStore::addGrant(const char* alias, uid_t granterUid, uid_t granteeUid) {
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return mGrants.put(granteeUid, alias, getUserStateByUid(granterUid)->getUserDirName(),
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granterUid);
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}
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bool KeyStore::removeGrant(const char* alias, const uid_t granterUid, const uid_t granteeUid) {
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return mGrants.removeByFileAlias(granteeUid, granterUid, alias);
|
|
}
|
|
void KeyStore::removeAllGrantsToUid(const uid_t granteeUid) {
|
|
mGrants.removeAllGrantsToUid(granteeUid);
|
|
}
|
|
|
|
ResponseCode KeyStore::importKey(const uint8_t* key, size_t keyLen, const char* filename,
|
|
uid_t userId, int32_t flags) {
|
|
Unique_PKCS8_PRIV_KEY_INFO pkcs8(d2i_PKCS8_PRIV_KEY_INFO(NULL, &key, keyLen));
|
|
if (!pkcs8.get()) {
|
|
return ResponseCode::SYSTEM_ERROR;
|
|
}
|
|
Unique_EVP_PKEY pkey(EVP_PKCS82PKEY(pkcs8.get()));
|
|
if (!pkey.get()) {
|
|
return ResponseCode::SYSTEM_ERROR;
|
|
}
|
|
int type = EVP_PKEY_type(pkey->type);
|
|
AuthorizationSet params;
|
|
add_legacy_key_authorizations(type, ¶ms);
|
|
switch (type) {
|
|
case EVP_PKEY_RSA:
|
|
params.push_back(TAG_ALGORITHM, Algorithm::RSA);
|
|
break;
|
|
case EVP_PKEY_EC:
|
|
params.push_back(TAG_ALGORITHM, Algorithm::EC);
|
|
break;
|
|
default:
|
|
ALOGW("Unsupported key type %d", type);
|
|
return ResponseCode::SYSTEM_ERROR;
|
|
}
|
|
|
|
AuthorizationSet opParams(params);
|
|
hidl_vec<uint8_t> blob;
|
|
|
|
ErrorCode error;
|
|
auto hidlCb = [&] (ErrorCode ret, const hidl_vec<uint8_t>& keyBlob,
|
|
const KeyCharacteristics& /* ignored */) {
|
|
error = ret;
|
|
if (error != ErrorCode::OK) return;
|
|
blob = keyBlob;
|
|
};
|
|
auto input = blob2hidlVec(key, keyLen);
|
|
|
|
ErrorCode rc = KS_HANDLE_HIDL_ERROR(
|
|
mDevice->importKey(params.hidl_data(), KeyFormat::PKCS8, input, hidlCb));
|
|
if (rc != ErrorCode::OK) return ResponseCode::SYSTEM_ERROR;
|
|
if (error != ErrorCode::OK) {
|
|
ALOGE("Keymaster error %d importing key pair", error);
|
|
return ResponseCode::SYSTEM_ERROR;
|
|
}
|
|
|
|
Blob keyBlob(&blob[0], blob.size(), NULL, 0, TYPE_KEYMASTER_10);
|
|
|
|
keyBlob.setEncrypted(flags & KEYSTORE_FLAG_ENCRYPTED);
|
|
keyBlob.setFallback(false);
|
|
|
|
return put(filename, &keyBlob, userId);
|
|
}
|
|
|
|
bool KeyStore::isHardwareBacked(const android::String16& /*keyType*/) const {
|
|
using ::android::hardware::hidl_string;
|
|
if (mDevice == NULL) {
|
|
ALOGW("can't get keymaster device");
|
|
return false;
|
|
}
|
|
|
|
bool isSecure = false;
|
|
auto hidlcb = [&] (bool _isSecure, bool, bool, bool, bool, const hidl_string&,
|
|
const hidl_string&) {
|
|
isSecure = _isSecure;
|
|
};
|
|
auto rc = mDevice->getHardwareFeatures(hidlcb);
|
|
if (!rc.isOk()) {
|
|
ALOGE("Communication with keymaster HAL failed while retrieving hardware features (%s)",
|
|
rc.description().c_str());
|
|
return false;
|
|
}
|
|
return isSecure;
|
|
}
|
|
|
|
ResponseCode KeyStore::getKeyForName(Blob* keyBlob, const android::String8& keyName,
|
|
const uid_t uid, const BlobType type) {
|
|
auto filepath8 = getBlobFileNameIfExists(keyName, uid, type);
|
|
uid_t userId = get_user_id(uid);
|
|
|
|
if (filepath8.isOk())
|
|
return get(filepath8.value().string(), keyBlob, type, userId);
|
|
|
|
return ResponseCode::KEY_NOT_FOUND;
|
|
}
|
|
|
|
UserState* KeyStore::getUserState(uid_t userId) {
|
|
for (android::Vector<UserState*>::iterator it(mMasterKeys.begin()); it != mMasterKeys.end();
|
|
it++) {
|
|
UserState* state = *it;
|
|
if (state->getUserId() == userId) {
|
|
return state;
|
|
}
|
|
}
|
|
|
|
UserState* userState = new UserState(userId);
|
|
if (!userState->initialize()) {
|
|
/* There's not much we can do if initialization fails. Trying to
|
|
* unlock the keystore for that user will fail as well, so any
|
|
* subsequent request for this user will just return SYSTEM_ERROR.
|
|
*/
|
|
ALOGE("User initialization failed for %u; subsuquent operations will fail", userId);
|
|
}
|
|
mMasterKeys.add(userState);
|
|
return userState;
|
|
}
|
|
|
|
UserState* KeyStore::getUserStateByUid(uid_t uid) {
|
|
uid_t userId = get_user_id(uid);
|
|
return getUserState(userId);
|
|
}
|
|
|
|
const UserState* KeyStore::getUserState(uid_t userId) const {
|
|
for (android::Vector<UserState*>::const_iterator it(mMasterKeys.begin());
|
|
it != mMasterKeys.end(); it++) {
|
|
UserState* state = *it;
|
|
if (state->getUserId() == userId) {
|
|
return state;
|
|
}
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
const UserState* KeyStore::getUserStateByUid(uid_t uid) const {
|
|
uid_t userId = get_user_id(uid);
|
|
return getUserState(userId);
|
|
}
|
|
|
|
bool KeyStore::upgradeBlob(const char* filename, Blob* blob, const uint8_t oldVersion,
|
|
const BlobType type, uid_t userId) {
|
|
bool updated = false;
|
|
uint8_t version = oldVersion;
|
|
|
|
/* From V0 -> V1: All old types were unknown */
|
|
if (version == 0) {
|
|
ALOGV("upgrading to version 1 and setting type %d", type);
|
|
|
|
blob->setType(type);
|
|
if (type == TYPE_KEY_PAIR) {
|
|
importBlobAsKey(blob, filename, userId);
|
|
}
|
|
version = 1;
|
|
updated = true;
|
|
}
|
|
|
|
/* From V1 -> V2: All old keys were encrypted */
|
|
if (version == 1) {
|
|
ALOGV("upgrading to version 2");
|
|
|
|
blob->setEncrypted(true);
|
|
version = 2;
|
|
updated = true;
|
|
}
|
|
|
|
/*
|
|
* If we've updated, set the key blob to the right version
|
|
* and write it.
|
|
*/
|
|
if (updated) {
|
|
ALOGV("updated and writing file %s", filename);
|
|
blob->setVersion(version);
|
|
}
|
|
|
|
return updated;
|
|
}
|
|
|
|
struct BIO_Delete {
|
|
void operator()(BIO* p) const { BIO_free(p); }
|
|
};
|
|
typedef std::unique_ptr<BIO, BIO_Delete> Unique_BIO;
|
|
|
|
ResponseCode KeyStore::importBlobAsKey(Blob* blob, const char* filename, uid_t userId) {
|
|
// We won't even write to the blob directly with this BIO, so const_cast is okay.
|
|
Unique_BIO b(BIO_new_mem_buf(const_cast<uint8_t*>(blob->getValue()), blob->getLength()));
|
|
if (b.get() == NULL) {
|
|
ALOGE("Problem instantiating BIO");
|
|
return ResponseCode::SYSTEM_ERROR;
|
|
}
|
|
|
|
Unique_EVP_PKEY pkey(PEM_read_bio_PrivateKey(b.get(), NULL, NULL, NULL));
|
|
if (pkey.get() == NULL) {
|
|
ALOGE("Couldn't read old PEM file");
|
|
return ResponseCode::SYSTEM_ERROR;
|
|
}
|
|
|
|
Unique_PKCS8_PRIV_KEY_INFO pkcs8(EVP_PKEY2PKCS8(pkey.get()));
|
|
int len = i2d_PKCS8_PRIV_KEY_INFO(pkcs8.get(), NULL);
|
|
if (len < 0) {
|
|
ALOGE("Couldn't measure PKCS#8 length");
|
|
return ResponseCode::SYSTEM_ERROR;
|
|
}
|
|
|
|
std::unique_ptr<unsigned char[]> pkcs8key(new unsigned char[len]);
|
|
uint8_t* tmp = pkcs8key.get();
|
|
if (i2d_PKCS8_PRIV_KEY_INFO(pkcs8.get(), &tmp) != len) {
|
|
ALOGE("Couldn't convert to PKCS#8");
|
|
return ResponseCode::SYSTEM_ERROR;
|
|
}
|
|
|
|
ResponseCode rc = importKey(pkcs8key.get(), len, filename, userId,
|
|
blob->isEncrypted() ? KEYSTORE_FLAG_ENCRYPTED : KEYSTORE_FLAG_NONE);
|
|
if (rc != ResponseCode::NO_ERROR) {
|
|
return rc;
|
|
}
|
|
|
|
return get(filename, blob, TYPE_KEY_PAIR, userId);
|
|
}
|
|
|
|
void KeyStore::readMetaData() {
|
|
int in = TEMP_FAILURE_RETRY(open(sMetaDataFile, O_RDONLY));
|
|
if (in < 0) {
|
|
return;
|
|
}
|
|
size_t fileLength = readFully(in, (uint8_t*)&mMetaData, sizeof(mMetaData));
|
|
if (fileLength != sizeof(mMetaData)) {
|
|
ALOGI("Metadata file is %zd bytes (%zd experted); upgrade?", fileLength, sizeof(mMetaData));
|
|
}
|
|
close(in);
|
|
}
|
|
|
|
void KeyStore::writeMetaData() {
|
|
const char* tmpFileName = ".metadata.tmp";
|
|
int out =
|
|
TEMP_FAILURE_RETRY(open(tmpFileName, O_WRONLY | O_TRUNC | O_CREAT, S_IRUSR | S_IWUSR));
|
|
if (out < 0) {
|
|
ALOGE("couldn't write metadata file: %s", strerror(errno));
|
|
return;
|
|
}
|
|
size_t fileLength = writeFully(out, (uint8_t*)&mMetaData, sizeof(mMetaData));
|
|
if (fileLength != sizeof(mMetaData)) {
|
|
ALOGI("Could only write %zd bytes to metadata file (%zd expected)", fileLength,
|
|
sizeof(mMetaData));
|
|
}
|
|
close(out);
|
|
rename(tmpFileName, sMetaDataFile);
|
|
}
|
|
|
|
bool KeyStore::upgradeKeystore() {
|
|
bool upgraded = false;
|
|
|
|
if (mMetaData.version == 0) {
|
|
UserState* userState = getUserStateByUid(0);
|
|
|
|
// Initialize first so the directory is made.
|
|
userState->initialize();
|
|
|
|
// Migrate the old .masterkey file to user 0.
|
|
if (access(sOldMasterKey, R_OK) == 0) {
|
|
if (rename(sOldMasterKey, userState->getMasterKeyFileName()) < 0) {
|
|
ALOGE("couldn't migrate old masterkey: %s", strerror(errno));
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// Initialize again in case we had a key.
|
|
userState->initialize();
|
|
|
|
// Try to migrate existing keys.
|
|
DIR* dir = opendir(".");
|
|
if (!dir) {
|
|
// Give up now; maybe we can upgrade later.
|
|
ALOGE("couldn't open keystore's directory; something is wrong");
|
|
return false;
|
|
}
|
|
|
|
struct dirent* file;
|
|
while ((file = readdir(dir)) != NULL) {
|
|
// We only care about files.
|
|
if (file->d_type != DT_REG) {
|
|
continue;
|
|
}
|
|
|
|
// Skip anything that starts with a "."
|
|
if (file->d_name[0] == '.') {
|
|
continue;
|
|
}
|
|
|
|
// Find the current file's user.
|
|
char* end;
|
|
unsigned long thisUid = strtoul(file->d_name, &end, 10);
|
|
if (end[0] != '_' || end[1] == 0) {
|
|
continue;
|
|
}
|
|
UserState* otherUser = getUserStateByUid(thisUid);
|
|
if (otherUser->getUserId() != 0) {
|
|
unlinkat(dirfd(dir), file->d_name, 0);
|
|
}
|
|
|
|
// Rename the file into user directory.
|
|
DIR* otherdir = opendir(otherUser->getUserDirName());
|
|
if (otherdir == NULL) {
|
|
ALOGW("couldn't open user directory for rename");
|
|
continue;
|
|
}
|
|
if (renameat(dirfd(dir), file->d_name, dirfd(otherdir), file->d_name) < 0) {
|
|
ALOGW("couldn't rename blob: %s: %s", file->d_name, strerror(errno));
|
|
}
|
|
closedir(otherdir);
|
|
}
|
|
closedir(dir);
|
|
|
|
mMetaData.version = 1;
|
|
upgraded = true;
|
|
}
|
|
|
|
return upgraded;
|
|
}
|