| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "sync/internal_api/sync_encryption_handler_impl.h" |
| |
| #include <queue> |
| #include <string> |
| |
| #include "base/base64.h" |
| #include "base/bind.h" |
| #include "base/message_loop.h" |
| #include "base/time.h" |
| #include "base/tracked_objects.h" |
| #include "base/metrics/histogram.h" |
| #include "sync/internal_api/public/read_node.h" |
| #include "sync/internal_api/public/read_transaction.h" |
| #include "sync/internal_api/public/user_share.h" |
| #include "sync/internal_api/public/util/experiments.h" |
| #include "sync/internal_api/public/write_node.h" |
| #include "sync/internal_api/public/write_transaction.h" |
| #include "sync/internal_api/public/util/sync_string_conversions.h" |
| #include "sync/protocol/encryption.pb.h" |
| #include "sync/protocol/nigori_specifics.pb.h" |
| #include "sync/protocol/sync.pb.h" |
| #include "sync/syncable/base_transaction.h" |
| #include "sync/syncable/directory.h" |
| #include "sync/syncable/entry.h" |
| #include "sync/syncable/nigori_util.h" |
| #include "sync/util/cryptographer.h" |
| #include "sync/util/time.h" |
| |
| namespace syncer { |
| |
| namespace { |
| |
| // The maximum number of times we will automatically overwrite the nigori node |
| // because the encryption keys don't match (per chrome instantiation). |
| // We protect ourselves against nigori rollbacks, but it's possible two |
| // different clients might have contrasting view of what the nigori node state |
| // should be, in which case they might ping pong (see crbug.com/119207). |
| static const int kNigoriOverwriteLimit = 10; |
| |
| // The new passphrase state is sufficient to determine whether a nigori node |
| // is migrated to support keystore encryption. In addition though, we also |
| // want to verify the conditions for proper keystore encryption functionality. |
| // 1. Passphrase state is set. |
| // 2. Migration time is set. |
| // 3. Frozen keybag is true |
| // 4. If passphrase state is keystore, keystore_decryptor_token is set. |
| bool IsNigoriMigratedToKeystore(const sync_pb::NigoriSpecifics& nigori) { |
| if (!nigori.has_passphrase_type()) |
| return false; |
| if (!nigori.has_keystore_migration_time()) |
| return false; |
| if (!nigori.keybag_is_frozen()) |
| return false; |
| if (nigori.passphrase_type() == |
| sync_pb::NigoriSpecifics::IMPLICIT_PASSPHRASE) |
| return false; |
| if (nigori.passphrase_type() == |
| sync_pb::NigoriSpecifics::KEYSTORE_PASSPHRASE && |
| nigori.keystore_decryptor_token().blob().empty()) |
| return false; |
| if (!nigori.has_keystore_migration_time()) |
| return false; |
| return true; |
| } |
| |
| PassphraseType ProtoPassphraseTypeToEnum( |
| sync_pb::NigoriSpecifics::PassphraseType type) { |
| switch(type) { |
| case sync_pb::NigoriSpecifics::IMPLICIT_PASSPHRASE: |
| return IMPLICIT_PASSPHRASE; |
| case sync_pb::NigoriSpecifics::KEYSTORE_PASSPHRASE: |
| return KEYSTORE_PASSPHRASE; |
| case sync_pb::NigoriSpecifics::CUSTOM_PASSPHRASE: |
| return CUSTOM_PASSPHRASE; |
| case sync_pb::NigoriSpecifics::FROZEN_IMPLICIT_PASSPHRASE: |
| return FROZEN_IMPLICIT_PASSPHRASE; |
| default: |
| NOTREACHED(); |
| return IMPLICIT_PASSPHRASE; |
| }; |
| } |
| |
| sync_pb::NigoriSpecifics::PassphraseType |
| EnumPassphraseTypeToProto(PassphraseType type) { |
| switch(type) { |
| case IMPLICIT_PASSPHRASE: |
| return sync_pb::NigoriSpecifics::IMPLICIT_PASSPHRASE; |
| case KEYSTORE_PASSPHRASE: |
| return sync_pb::NigoriSpecifics::KEYSTORE_PASSPHRASE; |
| case CUSTOM_PASSPHRASE: |
| return sync_pb::NigoriSpecifics::CUSTOM_PASSPHRASE; |
| case FROZEN_IMPLICIT_PASSPHRASE: |
| return sync_pb::NigoriSpecifics::FROZEN_IMPLICIT_PASSPHRASE; |
| default: |
| NOTREACHED(); |
| return sync_pb::NigoriSpecifics::IMPLICIT_PASSPHRASE;; |
| }; |
| } |
| |
| bool IsExplicitPassphrase(PassphraseType type) { |
| return type == CUSTOM_PASSPHRASE || type == FROZEN_IMPLICIT_PASSPHRASE; |
| } |
| |
| } // namespace |
| |
| SyncEncryptionHandlerImpl::Vault::Vault( |
| Encryptor* encryptor, |
| ModelTypeSet encrypted_types) |
| : cryptographer(encryptor), |
| encrypted_types(encrypted_types) { |
| } |
| |
| SyncEncryptionHandlerImpl::Vault::~Vault() { |
| } |
| |
| SyncEncryptionHandlerImpl::SyncEncryptionHandlerImpl( |
| UserShare* user_share, |
| Encryptor* encryptor, |
| const std::string& restored_key_for_bootstrapping, |
| const std::string& restored_keystore_key_for_bootstrapping) |
| : weak_ptr_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)), |
| user_share_(user_share), |
| vault_unsafe_(encryptor, SensitiveTypes()), |
| encrypt_everything_(false), |
| passphrase_type_(IMPLICIT_PASSPHRASE), |
| keystore_key_(restored_keystore_key_for_bootstrapping), |
| nigori_overwrite_count_(0) { |
| // We only bootstrap the user provided passphrase. The keystore key is handled |
| // at Init time once we're sure the nigori is downloaded. |
| vault_unsafe_.cryptographer.Bootstrap(restored_key_for_bootstrapping); |
| } |
| |
| SyncEncryptionHandlerImpl::~SyncEncryptionHandlerImpl() {} |
| |
| void SyncEncryptionHandlerImpl::AddObserver(Observer* observer) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| DCHECK(!observers_.HasObserver(observer)); |
| observers_.AddObserver(observer); |
| } |
| |
| void SyncEncryptionHandlerImpl::RemoveObserver(Observer* observer) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| DCHECK(observers_.HasObserver(observer)); |
| observers_.RemoveObserver(observer); |
| } |
| |
| void SyncEncryptionHandlerImpl::Init() { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| WriteTransaction trans(FROM_HERE, user_share_); |
| WriteNode node(&trans); |
| |
| if (node.InitByTagLookup(kNigoriTag) != BaseNode::INIT_OK) |
| return; |
| if (!ApplyNigoriUpdateImpl(node.GetNigoriSpecifics(), |
| trans.GetWrappedTrans())) { |
| WriteEncryptionStateToNigori(&trans); |
| } |
| |
| // Always trigger an encrypted types and cryptographer state change event at |
| // init time so observers get the initial values. |
| FOR_EACH_OBSERVER( |
| Observer, observers_, |
| OnEncryptedTypesChanged( |
| UnlockVault(trans.GetWrappedTrans()).encrypted_types, |
| encrypt_everything_)); |
| FOR_EACH_OBSERVER( |
| SyncEncryptionHandler::Observer, |
| observers_, |
| OnCryptographerStateChanged( |
| &UnlockVaultMutable(trans.GetWrappedTrans())->cryptographer)); |
| |
| // If the cryptographer is not ready (either it has pending keys or we |
| // failed to initialize it), we don't want to try and re-encrypt the data. |
| // If we had encrypted types, the DataTypeManager will block, preventing |
| // sync from happening until the the passphrase is provided. |
| if (UnlockVault(trans.GetWrappedTrans()).cryptographer.is_ready()) |
| ReEncryptEverything(&trans); |
| } |
| |
| void SyncEncryptionHandlerImpl::SetEncryptionPassphrase( |
| const std::string& passphrase, |
| bool is_explicit) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| // We do not accept empty passphrases. |
| if (passphrase.empty()) { |
| NOTREACHED() << "Cannot encrypt with an empty passphrase."; |
| return; |
| } |
| |
| // All accesses to the cryptographer are protected by a transaction. |
| WriteTransaction trans(FROM_HERE, user_share_); |
| KeyParams key_params = {"localhost", "dummy", passphrase}; |
| WriteNode node(&trans); |
| if (node.InitByTagLookup(kNigoriTag) != BaseNode::INIT_OK) { |
| NOTREACHED(); |
| return; |
| } |
| |
| Cryptographer* cryptographer = |
| &UnlockVaultMutable(trans.GetWrappedTrans())->cryptographer; |
| |
| // Once we've migrated to keystore, the only way to set a passphrase for |
| // encryption is to set a custom passphrase. |
| if (IsNigoriMigratedToKeystore(node.GetNigoriSpecifics())) { |
| if (!is_explicit) { |
| DCHECK(cryptographer->is_ready()); |
| // The user is setting a new implicit passphrase. At this point we don't |
| // care, so drop it on the floor. This is safe because if we have a |
| // migrated nigori node, then we don't need to create an initial |
| // encryption key. |
| LOG(WARNING) << "Ignoring new implicit passphrase. Keystore migration " |
| << "already performed."; |
| return; |
| } |
| // Will fail if we already have an explicit passphrase or we have pending |
| // keys. |
| SetCustomPassphrase(passphrase, &trans, &node); |
| return; |
| } |
| |
| std::string bootstrap_token; |
| sync_pb::EncryptedData pending_keys; |
| if (cryptographer->has_pending_keys()) |
| pending_keys = cryptographer->GetPendingKeys(); |
| bool success = false; |
| |
| // There are six cases to handle here: |
| // 1. The user has no pending keys and is setting their current GAIA password |
| // as the encryption passphrase. This happens either during first time sync |
| // with a clean profile, or after re-authenticating on a profile that was |
| // already signed in with the cryptographer ready. |
| // 2. The user has no pending keys, and is overwriting an (already provided) |
| // implicit passphrase with an explicit (custom) passphrase. |
| // 3. The user has pending keys for an explicit passphrase that is somehow set |
| // to their current GAIA passphrase. |
| // 4. The user has pending keys encrypted with their current GAIA passphrase |
| // and the caller passes in the current GAIA passphrase. |
| // 5. The user has pending keys encrypted with an older GAIA passphrase |
| // and the caller passes in the current GAIA passphrase. |
| // 6. The user has previously done encryption with an explicit passphrase. |
| // Furthermore, we enforce the fact that the bootstrap encryption token will |
| // always be derived from the newest GAIA password if the account is using |
| // an implicit passphrase (even if the data is encrypted with an old GAIA |
| // password). If the account is using an explicit (custom) passphrase, the |
| // bootstrap token will be derived from the most recently provided explicit |
| // passphrase (that was able to decrypt the data). |
| if (!IsExplicitPassphrase(passphrase_type_)) { |
| if (!cryptographer->has_pending_keys()) { |
| if (cryptographer->AddKey(key_params)) { |
| // Case 1 and 2. We set a new GAIA passphrase when there are no pending |
| // keys (1), or overwriting an implicit passphrase with a new explicit |
| // one (2) when there are no pending keys. |
| if (is_explicit) { |
| DVLOG(1) << "Setting explicit passphrase for encryption."; |
| passphrase_type_ = CUSTOM_PASSPHRASE; |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnPassphraseTypeChanged(passphrase_type_)); |
| } else { |
| DVLOG(1) << "Setting implicit passphrase for encryption."; |
| } |
| cryptographer->GetBootstrapToken(&bootstrap_token); |
| success = true; |
| } else { |
| NOTREACHED() << "Failed to add key to cryptographer."; |
| success = false; |
| } |
| } else { // cryptographer->has_pending_keys() == true |
| if (is_explicit) { |
| // This can only happen if the nigori node is updated with a new |
| // implicit passphrase while a client is attempting to set a new custom |
| // passphrase (race condition). |
| DVLOG(1) << "Failing because an implicit passphrase is already set."; |
| success = false; |
| } else { // is_explicit == false |
| if (cryptographer->DecryptPendingKeys(key_params)) { |
| // Case 4. We successfully decrypted with the implicit GAIA passphrase |
| // passed in. |
| DVLOG(1) << "Implicit internal passphrase accepted for decryption."; |
| cryptographer->GetBootstrapToken(&bootstrap_token); |
| success = true; |
| } else { |
| // Case 5. Encryption was done with an old GAIA password, but we were |
| // provided with the current GAIA password. We need to generate a new |
| // bootstrap token to preserve it. We build a temporary cryptographer |
| // to allow us to extract these params without polluting our current |
| // cryptographer. |
| DVLOG(1) << "Implicit internal passphrase failed to decrypt, adding " |
| << "anyways as default passphrase and persisting via " |
| << "bootstrap token."; |
| Cryptographer temp_cryptographer(cryptographer->encryptor()); |
| temp_cryptographer.AddKey(key_params); |
| temp_cryptographer.GetBootstrapToken(&bootstrap_token); |
| // We then set the new passphrase as the default passphrase of the |
| // real cryptographer, even though we have pending keys. This is safe, |
| // as although Cryptographer::is_initialized() will now be true, |
| // is_ready() will remain false due to having pending keys. |
| cryptographer->AddKey(key_params); |
| success = false; |
| } |
| } // is_explicit |
| } // cryptographer->has_pending_keys() |
| } else { // IsExplicitPassphrase(passphrase_type_) == true. |
| // Case 6. We do not want to override a previously set explicit passphrase, |
| // so we return a failure. |
| DVLOG(1) << "Failing because an explicit passphrase is already set."; |
| success = false; |
| } |
| |
| DVLOG_IF(1, !success) |
| << "Failure in SetEncryptionPassphrase; notifying and returning."; |
| DVLOG_IF(1, success) |
| << "Successfully set encryption passphrase; updating nigori and " |
| "reencrypting."; |
| |
| FinishSetPassphrase(success, bootstrap_token, &trans, &node); |
| } |
| |
| void SyncEncryptionHandlerImpl::SetDecryptionPassphrase( |
| const std::string& passphrase) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| // We do not accept empty passphrases. |
| if (passphrase.empty()) { |
| NOTREACHED() << "Cannot decrypt with an empty passphrase."; |
| return; |
| } |
| |
| // All accesses to the cryptographer are protected by a transaction. |
| WriteTransaction trans(FROM_HERE, user_share_); |
| KeyParams key_params = {"localhost", "dummy", passphrase}; |
| WriteNode node(&trans); |
| if (node.InitByTagLookup(kNigoriTag) != BaseNode::INIT_OK) { |
| NOTREACHED(); |
| return; |
| } |
| |
| // Once we've migrated to keystore, we're only ever decrypting keys derived |
| // from an explicit passphrase. But, for clients without a keystore key yet |
| // (either not on by default or failed to download one), we still support |
| // decrypting with a gaia passphrase, and therefore bypass the |
| // DecryptPendingKeysWithExplicitPassphrase logic. |
| if (IsNigoriMigratedToKeystore(node.GetNigoriSpecifics()) && |
| IsExplicitPassphrase(passphrase_type_)) { |
| DecryptPendingKeysWithExplicitPassphrase(passphrase, &trans, &node); |
| return; |
| } |
| |
| Cryptographer* cryptographer = |
| &UnlockVaultMutable(trans.GetWrappedTrans())->cryptographer; |
| if (!cryptographer->has_pending_keys()) { |
| // Note that this *can* happen in a rare situation where data is |
| // re-encrypted on another client while a SetDecryptionPassphrase() call is |
| // in-flight on this client. It is rare enough that we choose to do nothing. |
| NOTREACHED() << "Attempt to set decryption passphrase failed because there " |
| << "were no pending keys."; |
| return; |
| } |
| |
| std::string bootstrap_token; |
| sync_pb::EncryptedData pending_keys; |
| pending_keys = cryptographer->GetPendingKeys(); |
| bool success = false; |
| |
| // There are three cases to handle here: |
| // 7. We're using the current GAIA password to decrypt the pending keys. This |
| // happens when signing in to an account with a previously set implicit |
| // passphrase, where the data is already encrypted with the newest GAIA |
| // password. |
| // 8. The user is providing an old GAIA password to decrypt the pending keys. |
| // In this case, the user is using an implicit passphrase, but has changed |
| // their password since they last encrypted their data, and therefore |
| // their current GAIA password was unable to decrypt the data. This will |
| // happen when the user is setting up a new profile with a previously |
| // encrypted account (after changing passwords). |
| // 9. The user is providing a previously set explicit passphrase to decrypt |
| // the pending keys. |
| if (!IsExplicitPassphrase(passphrase_type_)) { |
| if (cryptographer->is_initialized()) { |
| // We only want to change the default encryption key to the pending |
| // one if the pending keybag already contains the current default. |
| // This covers the case where a different client re-encrypted |
| // everything with a newer gaia passphrase (and hence the keybag |
| // contains keys from all previously used gaia passphrases). |
| // Otherwise, we're in a situation where the pending keys are |
| // encrypted with an old gaia passphrase, while the default is the |
| // current gaia passphrase. In that case, we preserve the default. |
| Cryptographer temp_cryptographer(cryptographer->encryptor()); |
| temp_cryptographer.SetPendingKeys(cryptographer->GetPendingKeys()); |
| if (temp_cryptographer.DecryptPendingKeys(key_params)) { |
| // Check to see if the pending bag of keys contains the current |
| // default key. |
| sync_pb::EncryptedData encrypted; |
| cryptographer->GetKeys(&encrypted); |
| if (temp_cryptographer.CanDecrypt(encrypted)) { |
| DVLOG(1) << "Implicit user provided passphrase accepted for " |
| << "decryption, overwriting default."; |
| // Case 7. The pending keybag contains the current default. Go ahead |
| // and update the cryptographer, letting the default change. |
| cryptographer->DecryptPendingKeys(key_params); |
| cryptographer->GetBootstrapToken(&bootstrap_token); |
| success = true; |
| } else { |
| // Case 8. The pending keybag does not contain the current default |
| // encryption key. We decrypt the pending keys here, and in |
| // FinishSetPassphrase, re-encrypt everything with the current GAIA |
| // passphrase instead of the passphrase just provided by the user. |
| DVLOG(1) << "Implicit user provided passphrase accepted for " |
| << "decryption, restoring implicit internal passphrase " |
| << "as default."; |
| std::string bootstrap_token_from_current_key; |
| cryptographer->GetBootstrapToken( |
| &bootstrap_token_from_current_key); |
| cryptographer->DecryptPendingKeys(key_params); |
| // Overwrite the default from the pending keys. |
| cryptographer->AddKeyFromBootstrapToken( |
| bootstrap_token_from_current_key); |
| success = true; |
| } |
| } else { // !temp_cryptographer.DecryptPendingKeys(..) |
| DVLOG(1) << "Implicit user provided passphrase failed to decrypt."; |
| success = false; |
| } // temp_cryptographer.DecryptPendingKeys(...) |
| } else { // cryptographer->is_initialized() == false |
| if (cryptographer->DecryptPendingKeys(key_params)) { |
| // This can happpen in two cases: |
| // - First time sync on android, where we'll never have a |
| // !user_provided passphrase. |
| // - This is a restart for a client that lost their bootstrap token. |
| // In both cases, we should go ahead and initialize the cryptographer |
| // and persist the new bootstrap token. |
| // |
| // Note: at this point, we cannot distinguish between cases 7 and 8 |
| // above. This user provided passphrase could be the current or the |
| // old. But, as long as we persist the token, there's nothing more |
| // we can do. |
| cryptographer->GetBootstrapToken(&bootstrap_token); |
| DVLOG(1) << "Implicit user provided passphrase accepted, initializing" |
| << " cryptographer."; |
| success = true; |
| } else { |
| DVLOG(1) << "Implicit user provided passphrase failed to decrypt."; |
| success = false; |
| } |
| } // cryptographer->is_initialized() |
| } else { // nigori_has_explicit_passphrase == true |
| // Case 9. Encryption was done with an explicit passphrase, and we decrypt |
| // with the passphrase provided by the user. |
| if (cryptographer->DecryptPendingKeys(key_params)) { |
| DVLOG(1) << "Explicit passphrase accepted for decryption."; |
| cryptographer->GetBootstrapToken(&bootstrap_token); |
| success = true; |
| } else { |
| DVLOG(1) << "Explicit passphrase failed to decrypt."; |
| success = false; |
| } |
| } // nigori_has_explicit_passphrase |
| |
| DVLOG_IF(1, !success) |
| << "Failure in SetDecryptionPassphrase; notifying and returning."; |
| DVLOG_IF(1, success) |
| << "Successfully set decryption passphrase; updating nigori and " |
| "reencrypting."; |
| |
| FinishSetPassphrase(success, bootstrap_token, &trans, &node); |
| } |
| |
| void SyncEncryptionHandlerImpl::EnableEncryptEverything() { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| WriteTransaction trans(FROM_HERE, user_share_); |
| DVLOG(1) << "Enabling encrypt everything."; |
| if (encrypt_everything_) |
| return; |
| EnableEncryptEverythingImpl(trans.GetWrappedTrans()); |
| WriteEncryptionStateToNigori(&trans); |
| if (UnlockVault(trans.GetWrappedTrans()).cryptographer.is_ready()) |
| ReEncryptEverything(&trans); |
| } |
| |
| bool SyncEncryptionHandlerImpl::EncryptEverythingEnabled() const { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| return encrypt_everything_; |
| } |
| |
| PassphraseType SyncEncryptionHandlerImpl::GetPassphraseType() const { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| return passphrase_type_; |
| } |
| |
| // Note: this is called from within a syncable transaction, so we need to post |
| // tasks if we want to do any work that creates a new sync_api transaction. |
| void SyncEncryptionHandlerImpl::ApplyNigoriUpdate( |
| const sync_pb::NigoriSpecifics& nigori, |
| syncable::BaseTransaction* const trans) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| DCHECK(trans); |
| if (!ApplyNigoriUpdateImpl(nigori, trans)) { |
| MessageLoop::current()->PostTask( |
| FROM_HERE, |
| base::Bind(&SyncEncryptionHandlerImpl::RewriteNigori, |
| weak_ptr_factory_.GetWeakPtr())); |
| } |
| |
| FOR_EACH_OBSERVER( |
| SyncEncryptionHandler::Observer, |
| observers_, |
| OnCryptographerStateChanged( |
| &UnlockVaultMutable(trans)->cryptographer)); |
| } |
| |
| void SyncEncryptionHandlerImpl::UpdateNigoriFromEncryptedTypes( |
| sync_pb::NigoriSpecifics* nigori, |
| syncable::BaseTransaction* const trans) const { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| syncable::UpdateNigoriFromEncryptedTypes(UnlockVault(trans).encrypted_types, |
| encrypt_everything_, |
| nigori); |
| } |
| |
| bool SyncEncryptionHandlerImpl::NeedKeystoreKey( |
| syncable::BaseTransaction* const trans) const { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| return keystore_key_.empty(); |
| } |
| |
| bool SyncEncryptionHandlerImpl::SetKeystoreKey( |
| const std::string& key, |
| syncable::BaseTransaction* const trans) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| if (!keystore_key_.empty() || key.empty()) |
| return false; |
| // Base64 encode so we can persist the keystore key directly via preferences. |
| if (!base::Base64Encode(key, &keystore_key_)) { |
| LOG(ERROR) << "Failed to base64 encode keystore key."; |
| keystore_key_ = ""; |
| return false; |
| } |
| |
| DVLOG(1) << "Keystore bootstrap token updated."; |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnBootstrapTokenUpdated(keystore_key_, |
| KEYSTORE_BOOTSTRAP_TOKEN)); |
| |
| Cryptographer* cryptographer = &UnlockVaultMutable(trans)->cryptographer; |
| syncable::Entry entry(trans, syncable::GET_BY_SERVER_TAG, kNigoriTag); |
| if (entry.good()) { |
| const sync_pb::NigoriSpecifics& nigori = |
| entry.Get(syncable::SPECIFICS).nigori(); |
| if (cryptographer->has_pending_keys() && |
| IsNigoriMigratedToKeystore(nigori) && |
| !nigori.keystore_decryptor_token().blob().empty()) { |
| // If the nigori is already migrated and we have pending keys, we might |
| // be able to decrypt them using the keystore decryptor token. |
| DecryptPendingKeysWithKeystoreKey(keystore_key_, |
| nigori.keystore_decryptor_token(), |
| cryptographer); |
| } else if (ShouldTriggerMigration(nigori, *cryptographer)) { |
| // We call rewrite nigori to attempt to trigger migration. |
| // Need to post a task to open a new sync_api transaction. |
| MessageLoop::current()->PostTask( |
| FROM_HERE, |
| base::Bind(&SyncEncryptionHandlerImpl::RewriteNigori, |
| weak_ptr_factory_.GetWeakPtr())); |
| } |
| } |
| |
| return true; |
| } |
| |
| ModelTypeSet SyncEncryptionHandlerImpl::GetEncryptedTypes( |
| syncable::BaseTransaction* const trans) const { |
| return UnlockVault(trans).encrypted_types; |
| } |
| |
| Cryptographer* SyncEncryptionHandlerImpl::GetCryptographerUnsafe() { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| return &vault_unsafe_.cryptographer; |
| } |
| |
| ModelTypeSet SyncEncryptionHandlerImpl::GetEncryptedTypesUnsafe() { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| return vault_unsafe_.encrypted_types; |
| } |
| |
| bool SyncEncryptionHandlerImpl::MigratedToKeystore() { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| ReadTransaction trans(FROM_HERE, user_share_); |
| ReadNode nigori_node(&trans); |
| if (nigori_node.InitByTagLookup(kNigoriTag) != BaseNode::INIT_OK) |
| return false; |
| return IsNigoriMigratedToKeystore(nigori_node.GetNigoriSpecifics()); |
| } |
| |
| base::Time SyncEncryptionHandlerImpl::migration_time() const { |
| return migration_time_; |
| } |
| |
| // This function iterates over all encrypted types. There are many scenarios in |
| // which data for some or all types is not currently available. In that case, |
| // the lookup of the root node will fail and we will skip encryption for that |
| // type. |
| void SyncEncryptionHandlerImpl::ReEncryptEverything( |
| WriteTransaction* trans) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| DCHECK(UnlockVault(trans->GetWrappedTrans()).cryptographer.is_ready()); |
| for (ModelTypeSet::Iterator iter = |
| UnlockVault(trans->GetWrappedTrans()).encrypted_types.First(); |
| iter.Good(); iter.Inc()) { |
| if (iter.Get() == PASSWORDS || IsControlType(iter.Get())) |
| continue; // These types handle encryption differently. |
| |
| ReadNode type_root(trans); |
| std::string tag = ModelTypeToRootTag(iter.Get()); |
| if (type_root.InitByTagLookup(tag) != BaseNode::INIT_OK) |
| continue; // Don't try to reencrypt if the type's data is unavailable. |
| |
| // Iterate through all children of this datatype. |
| std::queue<int64> to_visit; |
| int64 child_id = type_root.GetFirstChildId(); |
| to_visit.push(child_id); |
| while (!to_visit.empty()) { |
| child_id = to_visit.front(); |
| to_visit.pop(); |
| if (child_id == kInvalidId) |
| continue; |
| |
| WriteNode child(trans); |
| if (child.InitByIdLookup(child_id) != BaseNode::INIT_OK) { |
| NOTREACHED(); |
| continue; |
| } |
| if (child.GetIsFolder()) { |
| to_visit.push(child.GetFirstChildId()); |
| } |
| if (child.GetEntry()->Get(syncable::UNIQUE_SERVER_TAG).empty()) { |
| // Rewrite the specifics of the node with encrypted data if necessary |
| // (only rewrite the non-unique folders). |
| child.ResetFromSpecifics(); |
| } |
| to_visit.push(child.GetSuccessorId()); |
| } |
| } |
| |
| // Passwords are encrypted with their own legacy scheme. Passwords are always |
| // encrypted so we don't need to check GetEncryptedTypes() here. |
| ReadNode passwords_root(trans); |
| std::string passwords_tag = ModelTypeToRootTag(PASSWORDS); |
| if (passwords_root.InitByTagLookup(passwords_tag) == |
| BaseNode::INIT_OK) { |
| int64 child_id = passwords_root.GetFirstChildId(); |
| while (child_id != kInvalidId) { |
| WriteNode child(trans); |
| if (child.InitByIdLookup(child_id) != BaseNode::INIT_OK) { |
| NOTREACHED(); |
| return; |
| } |
| child.SetPasswordSpecifics(child.GetPasswordSpecifics()); |
| child_id = child.GetSuccessorId(); |
| } |
| } |
| |
| DVLOG(1) << "Re-encrypt everything complete."; |
| |
| // NOTE: We notify from within a transaction. |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnEncryptionComplete()); |
| } |
| |
| bool SyncEncryptionHandlerImpl::ApplyNigoriUpdateImpl( |
| const sync_pb::NigoriSpecifics& nigori, |
| syncable::BaseTransaction* const trans) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| DVLOG(1) << "Applying nigori node update."; |
| bool nigori_types_need_update = !UpdateEncryptedTypesFromNigori(nigori, |
| trans); |
| bool is_nigori_migrated = IsNigoriMigratedToKeystore(nigori); |
| if (is_nigori_migrated) { |
| DCHECK(nigori.has_keystore_migration_time()); |
| migration_time_ = ProtoTimeToTime(nigori.keystore_migration_time()); |
| PassphraseType nigori_passphrase_type = |
| ProtoPassphraseTypeToEnum(nigori.passphrase_type()); |
| |
| // Only update the local passphrase state if it's a valid transition: |
| // - implicit -> keystore |
| // - implicit -> frozen implicit |
| // - implicit -> custom |
| // - keystore -> custom |
| // Note: frozen implicit -> custom is not technically a valid transition, |
| // but we let it through here as well in case future versions do add support |
| // for this transition. |
| if (passphrase_type_ != nigori_passphrase_type && |
| nigori_passphrase_type != IMPLICIT_PASSPHRASE && |
| (passphrase_type_ == IMPLICIT_PASSPHRASE || |
| nigori_passphrase_type == CUSTOM_PASSPHRASE)) { |
| DVLOG(1) << "Changing passphrase state from " |
| << PassphraseTypeToString(passphrase_type_) |
| << " to " |
| << PassphraseTypeToString(nigori_passphrase_type); |
| passphrase_type_ = nigori_passphrase_type; |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnPassphraseTypeChanged(passphrase_type_)); |
| } |
| if (passphrase_type_ == KEYSTORE_PASSPHRASE && encrypt_everything_) { |
| // This is the case where another client that didn't support keystore |
| // encryption attempted to enable full encryption. We detect it |
| // and switch the passphrase type to frozen implicit passphrase instead |
| // due to full encryption not being compatible with keystore passphrase. |
| // Because the local passphrase type will not match the nigori passphrase |
| // type, we will trigger a rewrite and subsequently a re-migration. |
| DVLOG(1) << "Changing passphrase state to FROZEN_IMPLICIT_PASSPHRASE " |
| << "due to full encryption."; |
| passphrase_type_ = FROZEN_IMPLICIT_PASSPHRASE; |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnPassphraseTypeChanged(passphrase_type_)); |
| } |
| } else { |
| // It's possible that while we're waiting for migration a client that does |
| // not have keystore encryption enabled switches to a custom passphrase. |
| if (nigori.keybag_is_frozen() && |
| passphrase_type_ != CUSTOM_PASSPHRASE) { |
| passphrase_type_ = CUSTOM_PASSPHRASE; |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnPassphraseTypeChanged(passphrase_type_)); |
| } |
| } |
| |
| Cryptographer* cryptographer = &UnlockVaultMutable(trans)->cryptographer; |
| bool nigori_needs_new_keys = false; |
| if (!nigori.encryption_keybag().blob().empty()) { |
| // We only update the default key if this was a new explicit passphrase. |
| // Else, since it was decryptable, it must not have been a new key. |
| bool need_new_default_key = false; |
| if (is_nigori_migrated) { |
| need_new_default_key = IsExplicitPassphrase( |
| ProtoPassphraseTypeToEnum(nigori.passphrase_type())); |
| } else { |
| need_new_default_key = nigori.keybag_is_frozen(); |
| } |
| if (!AttemptToInstallKeybag(nigori.encryption_keybag(), |
| need_new_default_key, |
| cryptographer)) { |
| // Check to see if we can decrypt the keybag using the keystore decryptor |
| // token. |
| cryptographer->SetPendingKeys(nigori.encryption_keybag()); |
| if (!nigori.keystore_decryptor_token().blob().empty() && |
| !keystore_key_.empty()) { |
| if (DecryptPendingKeysWithKeystoreKey(keystore_key_, |
| nigori.keystore_decryptor_token(), |
| cryptographer)) { |
| nigori_needs_new_keys = |
| cryptographer->KeybagIsStale(nigori.encryption_keybag()); |
| } else { |
| LOG(ERROR) << "Failed to decrypt pending keys using keystore " |
| << "bootstrap key."; |
| } |
| } |
| } else { |
| // Keybag was installed. We write back our local keybag into the nigori |
| // node if the nigori node's keybag either contains less keys or |
| // has a different default key. |
| nigori_needs_new_keys = |
| cryptographer->KeybagIsStale(nigori.encryption_keybag()); |
| } |
| } else { |
| // The nigori node has an empty encryption keybag. Attempt to write our |
| // local encryption keys into it. |
| LOG(WARNING) << "Nigori had empty encryption keybag."; |
| nigori_needs_new_keys = true; |
| } |
| |
| // If we've completed a sync cycle and the cryptographer isn't ready |
| // yet or has pending keys, prompt the user for a passphrase. |
| if (cryptographer->has_pending_keys()) { |
| DVLOG(1) << "OnPassphraseRequired Sent"; |
| sync_pb::EncryptedData pending_keys = cryptographer->GetPendingKeys(); |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnPassphraseRequired(REASON_DECRYPTION, |
| pending_keys)); |
| } else if (!cryptographer->is_ready()) { |
| DVLOG(1) << "OnPassphraseRequired sent because cryptographer is not " |
| << "ready"; |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnPassphraseRequired(REASON_ENCRYPTION, |
| sync_pb::EncryptedData())); |
| } |
| |
| // Check if the current local encryption state is stricter/newer than the |
| // nigori state. If so, we need to overwrite the nigori node with the local |
| // state. |
| bool passphrase_type_matches = true; |
| if (!is_nigori_migrated) { |
| DCHECK(passphrase_type_ == CUSTOM_PASSPHRASE || |
| passphrase_type_ == IMPLICIT_PASSPHRASE); |
| passphrase_type_matches = |
| nigori.keybag_is_frozen() == IsExplicitPassphrase(passphrase_type_); |
| } else { |
| passphrase_type_matches = |
| (ProtoPassphraseTypeToEnum(nigori.passphrase_type()) == |
| passphrase_type_); |
| } |
| if (!passphrase_type_matches || |
| nigori.encrypt_everything() != encrypt_everything_ || |
| nigori_types_need_update || |
| nigori_needs_new_keys) { |
| DVLOG(1) << "Triggering nigori rewrite."; |
| return false; |
| } |
| return true; |
| } |
| |
| void SyncEncryptionHandlerImpl::RewriteNigori() { |
| DVLOG(1) << "Writing local encryption state into nigori."; |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| WriteTransaction trans(FROM_HERE, user_share_); |
| WriteEncryptionStateToNigori(&trans); |
| } |
| |
| void SyncEncryptionHandlerImpl::WriteEncryptionStateToNigori( |
| WriteTransaction* trans) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| WriteNode nigori_node(trans); |
| // This can happen in tests that don't have nigori nodes. |
| if (nigori_node.InitByTagLookup(kNigoriTag) != BaseNode::INIT_OK) |
| return; |
| |
| sync_pb::NigoriSpecifics nigori = nigori_node.GetNigoriSpecifics(); |
| const Cryptographer& cryptographer = |
| UnlockVault(trans->GetWrappedTrans()).cryptographer; |
| |
| // Will not do anything if we shouldn't or can't migrate. Otherwise |
| // migrates, writing the full encryption state as it does. |
| if (!AttemptToMigrateNigoriToKeystore(trans, &nigori_node)) { |
| if (cryptographer.is_ready() && |
| nigori_overwrite_count_ < kNigoriOverwriteLimit) { |
| // Does not modify the encrypted blob if the unencrypted data already |
| // matches what is about to be written. |
| sync_pb::EncryptedData original_keys = nigori.encryption_keybag(); |
| if (!cryptographer.GetKeys(nigori.mutable_encryption_keybag())) |
| NOTREACHED(); |
| |
| if (nigori.encryption_keybag().SerializeAsString() != |
| original_keys.SerializeAsString()) { |
| // We've updated the nigori node's encryption keys. In order to prevent |
| // a possible looping of two clients constantly overwriting each other, |
| // we limit the absolute number of overwrites per client instantiation. |
| nigori_overwrite_count_++; |
| UMA_HISTOGRAM_COUNTS("Sync.AutoNigoriOverwrites", |
| nigori_overwrite_count_); |
| } |
| |
| // Note: we don't try to set keybag_is_frozen here since if that |
| // is lost the user can always set it again (and we don't want to clobber |
| // any migration state). The main goal at this point is to preserve |
| // the encryption keys so all data remains decryptable. |
| } |
| syncable::UpdateNigoriFromEncryptedTypes( |
| UnlockVault(trans->GetWrappedTrans()).encrypted_types, |
| encrypt_everything_, |
| &nigori); |
| |
| // If nothing has changed, this is a no-op. |
| nigori_node.SetNigoriSpecifics(nigori); |
| } |
| } |
| |
| bool SyncEncryptionHandlerImpl::UpdateEncryptedTypesFromNigori( |
| const sync_pb::NigoriSpecifics& nigori, |
| syncable::BaseTransaction* const trans) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| ModelTypeSet* encrypted_types = &UnlockVaultMutable(trans)->encrypted_types; |
| if (nigori.encrypt_everything()) { |
| EnableEncryptEverythingImpl(trans); |
| DCHECK(encrypted_types->Equals(UserTypes())); |
| return true; |
| } else if (encrypt_everything_) { |
| DCHECK(encrypted_types->Equals(UserTypes())); |
| return false; |
| } |
| |
| ModelTypeSet nigori_encrypted_types; |
| nigori_encrypted_types = syncable::GetEncryptedTypesFromNigori(nigori); |
| nigori_encrypted_types.PutAll(SensitiveTypes()); |
| |
| // If anything more than the sensitive types were encrypted, and |
| // encrypt_everything is not explicitly set to false, we assume it means |
| // a client intended to enable encrypt everything. |
| if (!nigori.has_encrypt_everything() && |
| !Difference(nigori_encrypted_types, SensitiveTypes()).Empty()) { |
| if (!encrypt_everything_) { |
| encrypt_everything_ = true; |
| *encrypted_types = UserTypes(); |
| FOR_EACH_OBSERVER( |
| Observer, observers_, |
| OnEncryptedTypesChanged(*encrypted_types, encrypt_everything_)); |
| } |
| DCHECK(encrypted_types->Equals(UserTypes())); |
| return false; |
| } |
| |
| MergeEncryptedTypes(nigori_encrypted_types, trans); |
| return encrypted_types->Equals(nigori_encrypted_types); |
| } |
| |
| void SyncEncryptionHandlerImpl::SetCustomPassphrase( |
| const std::string& passphrase, |
| WriteTransaction* trans, |
| WriteNode* nigori_node) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| DCHECK(IsNigoriMigratedToKeystore(nigori_node->GetNigoriSpecifics())); |
| KeyParams key_params = {"localhost", "dummy", passphrase}; |
| |
| if (passphrase_type_ != KEYSTORE_PASSPHRASE) { |
| DVLOG(1) << "Failing to set a custom passphrase because one has already " |
| << "been set."; |
| FinishSetPassphrase(false, "", trans, nigori_node); |
| return; |
| } |
| |
| Cryptographer* cryptographer = |
| &UnlockVaultMutable(trans->GetWrappedTrans())->cryptographer; |
| if (cryptographer->has_pending_keys()) { |
| // This theoretically shouldn't happen, because the only way to have pending |
| // keys after migrating to keystore support is if a custom passphrase was |
| // set, which should update passpshrase_state_ and should be caught by the |
| // if statement above. For the sake of safety though, we check for it in |
| // case a client is misbehaving. |
| LOG(ERROR) << "Failing to set custom passphrase because of pending keys."; |
| FinishSetPassphrase(false, "", trans, nigori_node); |
| return; |
| } |
| |
| std::string bootstrap_token; |
| if (cryptographer->AddKey(key_params)) { |
| DVLOG(1) << "Setting custom passphrase."; |
| cryptographer->GetBootstrapToken(&bootstrap_token); |
| passphrase_type_ = CUSTOM_PASSPHRASE; |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnPassphraseTypeChanged(passphrase_type_)); |
| } else { |
| NOTREACHED() << "Failed to add key to cryptographer."; |
| return; |
| } |
| FinishSetPassphrase(true, bootstrap_token, trans, nigori_node); |
| } |
| |
| void SyncEncryptionHandlerImpl::DecryptPendingKeysWithExplicitPassphrase( |
| const std::string& passphrase, |
| WriteTransaction* trans, |
| WriteNode* nigori_node) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| DCHECK(IsExplicitPassphrase(passphrase_type_)); |
| KeyParams key_params = {"localhost", "dummy", passphrase}; |
| |
| Cryptographer* cryptographer = |
| &UnlockVaultMutable(trans->GetWrappedTrans())->cryptographer; |
| if (!cryptographer->has_pending_keys()) { |
| // Note that this *can* happen in a rare situation where data is |
| // re-encrypted on another client while a SetDecryptionPassphrase() call is |
| // in-flight on this client. It is rare enough that we choose to do nothing. |
| NOTREACHED() << "Attempt to set decryption passphrase failed because there " |
| << "were no pending keys."; |
| return; |
| } |
| |
| DCHECK(IsExplicitPassphrase(passphrase_type_)); |
| bool success = false; |
| std::string bootstrap_token; |
| if (cryptographer->DecryptPendingKeys(key_params)) { |
| DVLOG(1) << "Explicit passphrase accepted for decryption."; |
| cryptographer->GetBootstrapToken(&bootstrap_token); |
| success = true; |
| } else { |
| DVLOG(1) << "Explicit passphrase failed to decrypt."; |
| success = false; |
| } |
| if (success && !keystore_key_.empty()) { |
| // Should already be part of the encryption keybag, but we add it just |
| // in case. |
| KeyParams key_params = {"localhost", "dummy", keystore_key_}; |
| cryptographer->AddNonDefaultKey(key_params); |
| } |
| FinishSetPassphrase(success, bootstrap_token, trans, nigori_node); |
| } |
| |
| void SyncEncryptionHandlerImpl::FinishSetPassphrase( |
| bool success, |
| const std::string& bootstrap_token, |
| WriteTransaction* trans, |
| WriteNode* nigori_node) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| FOR_EACH_OBSERVER( |
| SyncEncryptionHandler::Observer, |
| observers_, |
| OnCryptographerStateChanged( |
| &UnlockVaultMutable(trans->GetWrappedTrans())->cryptographer)); |
| |
| // It's possible we need to change the bootstrap token even if we failed to |
| // set the passphrase (for example if we need to preserve the new GAIA |
| // passphrase). |
| if (!bootstrap_token.empty()) { |
| DVLOG(1) << "Passphrase bootstrap token updated."; |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnBootstrapTokenUpdated(bootstrap_token, |
| PASSPHRASE_BOOTSTRAP_TOKEN)); |
| } |
| |
| const Cryptographer& cryptographer = |
| UnlockVault(trans->GetWrappedTrans()).cryptographer; |
| if (!success) { |
| if (cryptographer.is_ready()) { |
| LOG(ERROR) << "Attempt to change passphrase failed while cryptographer " |
| << "was ready."; |
| } else if (cryptographer.has_pending_keys()) { |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnPassphraseRequired(REASON_DECRYPTION, |
| cryptographer.GetPendingKeys())); |
| } else { |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnPassphraseRequired(REASON_ENCRYPTION, |
| sync_pb::EncryptedData())); |
| } |
| return; |
| } |
| DCHECK(success); |
| DCHECK(cryptographer.is_ready()); |
| |
| // Will do nothing if we're already properly migrated or unable to migrate |
| // (in otherwords, if ShouldTriggerMigration is false). |
| // Otherwise will update the nigori node with the current migrated state, |
| // writing all encryption state as it does. |
| if (!AttemptToMigrateNigoriToKeystore(trans, nigori_node)) { |
| sync_pb::NigoriSpecifics nigori(nigori_node->GetNigoriSpecifics()); |
| // Does not modify nigori.encryption_keybag() if the original decrypted |
| // data was the same. |
| if (!cryptographer.GetKeys(nigori.mutable_encryption_keybag())) |
| NOTREACHED(); |
| if (IsNigoriMigratedToKeystore(nigori)) { |
| DCHECK(keystore_key_.empty() || IsExplicitPassphrase(passphrase_type_)); |
| DVLOG(1) << "Leaving nigori migration state untouched after setting" |
| << " passphrase."; |
| } else { |
| nigori.set_keybag_is_frozen( |
| IsExplicitPassphrase(passphrase_type_)); |
| } |
| nigori_node->SetNigoriSpecifics(nigori); |
| } |
| |
| // Must do this after OnPassphraseTypeChanged, in order to ensure the PSS |
| // checks the passphrase state after it has been set. |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnPassphraseAccepted()); |
| |
| // Does nothing if everything is already encrypted. |
| // TODO(zea): If we just migrated and enabled encryption, this will be |
| // redundant. Figure out a way to not do this unnecessarily. |
| ReEncryptEverything(trans); |
| } |
| |
| void SyncEncryptionHandlerImpl::MergeEncryptedTypes( |
| ModelTypeSet new_encrypted_types, |
| syncable::BaseTransaction* const trans) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| |
| // Only UserTypes may be encrypted. |
| DCHECK(UserTypes().HasAll(new_encrypted_types)); |
| |
| ModelTypeSet* encrypted_types = &UnlockVaultMutable(trans)->encrypted_types; |
| if (!encrypted_types->HasAll(new_encrypted_types)) { |
| *encrypted_types = new_encrypted_types; |
| FOR_EACH_OBSERVER( |
| Observer, observers_, |
| OnEncryptedTypesChanged(*encrypted_types, encrypt_everything_)); |
| } |
| } |
| |
| SyncEncryptionHandlerImpl::Vault* SyncEncryptionHandlerImpl::UnlockVaultMutable( |
| syncable::BaseTransaction* const trans) { |
| DCHECK_EQ(user_share_->directory.get(), trans->directory()); |
| return &vault_unsafe_; |
| } |
| |
| const SyncEncryptionHandlerImpl::Vault& SyncEncryptionHandlerImpl::UnlockVault( |
| syncable::BaseTransaction* const trans) const { |
| DCHECK_EQ(user_share_->directory.get(), trans->directory()); |
| return vault_unsafe_; |
| } |
| |
| bool SyncEncryptionHandlerImpl::ShouldTriggerMigration( |
| const sync_pb::NigoriSpecifics& nigori, |
| const Cryptographer& cryptographer) const { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| // TODO(zea): once we're willing to have the keystore key be the only |
| // encryption key, change this to !has_pending_keys(). For now, we need the |
| // cryptographer to be initialized with the current GAIA pass so that older |
| // clients (that don't have keystore support) can decrypt the keybag. |
| if (!cryptographer.is_ready()) |
| return false; |
| if (IsNigoriMigratedToKeystore(nigori)) { |
| // If the nigori is already migrated but does not reflect the explicit |
| // passphrase state, remigrate. Similarly, if the nigori has an explicit |
| // passphrase but does not have full encryption, or the nigori has an |
| // implicit passphrase but does have full encryption, re-migrate. |
| // Note that this is to defend against other clients without keystore |
| // encryption enabled transitioning to states that are no longer valid. |
| if (passphrase_type_ != KEYSTORE_PASSPHRASE && |
| nigori.passphrase_type() == |
| sync_pb::NigoriSpecifics::KEYSTORE_PASSPHRASE) { |
| return true; |
| } else if (IsExplicitPassphrase(passphrase_type_) && |
| !encrypt_everything_) { |
| return true; |
| } else if (passphrase_type_ == KEYSTORE_PASSPHRASE && |
| encrypt_everything_) { |
| return true; |
| } else if ( |
| cryptographer.is_ready() && |
| !cryptographer.CanDecryptUsingDefaultKey(nigori.encryption_keybag())) { |
| // We need to overwrite the keybag. This might involve overwriting the |
| // keystore decryptor too. |
| return true; |
| } else { |
| return false; |
| } |
| } else if (keystore_key_.empty()) { |
| // If we haven't already migrated, we don't want to do anything unless |
| // a keystore key is available (so that those clients without keystore |
| // encryption enabled aren't forced into new states, e.g. frozen implicit |
| // passphrase). |
| return false; |
| } |
| return true; |
| } |
| |
| bool SyncEncryptionHandlerImpl::AttemptToMigrateNigoriToKeystore( |
| WriteTransaction* trans, |
| WriteNode* nigori_node) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| const sync_pb::NigoriSpecifics& old_nigori = |
| nigori_node->GetNigoriSpecifics(); |
| Cryptographer* cryptographer = |
| &UnlockVaultMutable(trans->GetWrappedTrans())->cryptographer; |
| |
| if (!ShouldTriggerMigration(old_nigori, *cryptographer)) |
| return false; |
| |
| DVLOG(1) << "Starting nigori migration to keystore support."; |
| sync_pb::NigoriSpecifics migrated_nigori(old_nigori); |
| |
| PassphraseType new_passphrase_type = passphrase_type_; |
| bool new_encrypt_everything = encrypt_everything_; |
| if (encrypt_everything_ && !IsExplicitPassphrase(passphrase_type_)) { |
| DVLOG(1) << "Switching to frozen implicit passphrase due to already having " |
| << "full encryption."; |
| new_passphrase_type = FROZEN_IMPLICIT_PASSPHRASE; |
| migrated_nigori.clear_keystore_decryptor_token(); |
| } else if (IsExplicitPassphrase(passphrase_type_)) { |
| DVLOG_IF(1, !encrypt_everything_) << "Enabling encrypt everything due to " |
| << "explicit passphrase"; |
| new_encrypt_everything = true; |
| migrated_nigori.clear_keystore_decryptor_token(); |
| } else { |
| DCHECK(!encrypt_everything_); |
| new_passphrase_type = KEYSTORE_PASSPHRASE; |
| DVLOG(1) << "Switching to keystore passphrase state."; |
| } |
| migrated_nigori.set_encrypt_everything(new_encrypt_everything); |
| migrated_nigori.set_passphrase_type( |
| EnumPassphraseTypeToProto(new_passphrase_type)); |
| migrated_nigori.set_keybag_is_frozen(true); |
| |
| if (!keystore_key_.empty()) { |
| KeyParams key_params = {"localhost", "dummy", keystore_key_}; |
| if (!cryptographer->AddNonDefaultKey(key_params)) { |
| LOG(ERROR) << "Failed to add keystore key as non-default key."; |
| return false; |
| } |
| } |
| if (new_passphrase_type == KEYSTORE_PASSPHRASE && |
| !GetKeystoreDecryptor( |
| *cryptographer, |
| keystore_key_, |
| migrated_nigori.mutable_keystore_decryptor_token())) { |
| LOG(ERROR) << "Failed to extract keystore decryptor token."; |
| return false; |
| } |
| if (!cryptographer->GetKeys(migrated_nigori.mutable_encryption_keybag())) { |
| LOG(ERROR) << "Failed to extract encryption keybag."; |
| return false; |
| } |
| |
| if (migration_time_.is_null()) |
| migration_time_ = base::Time::Now(); |
| migrated_nigori.set_keystore_migration_time(TimeToProtoTime(migration_time_)); |
| |
| DVLOG(1) << "Completing nigori migration to keystore support."; |
| nigori_node->SetNigoriSpecifics(migrated_nigori); |
| |
| FOR_EACH_OBSERVER( |
| SyncEncryptionHandler::Observer, |
| observers_, |
| OnCryptographerStateChanged(cryptographer)); |
| if (passphrase_type_ != new_passphrase_type) { |
| passphrase_type_ = new_passphrase_type; |
| FOR_EACH_OBSERVER(SyncEncryptionHandler::Observer, observers_, |
| OnPassphraseTypeChanged(passphrase_type_)); |
| } |
| |
| if (new_encrypt_everything && !encrypt_everything_) { |
| EnableEncryptEverythingImpl(trans->GetWrappedTrans()); |
| ReEncryptEverything(trans); |
| } |
| return true; |
| } |
| |
| bool SyncEncryptionHandlerImpl::GetKeystoreDecryptor( |
| const Cryptographer& cryptographer, |
| const std::string& keystore_key, |
| sync_pb::EncryptedData* encrypted_blob) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| DCHECK(!keystore_key.empty()); |
| DCHECK(cryptographer.is_ready()); |
| std::string serialized_nigori; |
| serialized_nigori = cryptographer.GetDefaultNigoriKey(); |
| if (serialized_nigori.empty()) { |
| LOG(ERROR) << "Failed to get cryptographer bootstrap token."; |
| return false; |
| } |
| Cryptographer temp_cryptographer(cryptographer.encryptor()); |
| KeyParams key_params = {"localhost", "dummy", keystore_key}; |
| if (!temp_cryptographer.AddKey(key_params)) |
| return false; |
| if (!temp_cryptographer.EncryptString(serialized_nigori, encrypted_blob)) |
| return false; |
| return true; |
| } |
| |
| bool SyncEncryptionHandlerImpl::AttemptToInstallKeybag( |
| const sync_pb::EncryptedData& keybag, |
| bool update_default, |
| Cryptographer* cryptographer) { |
| if (!cryptographer->CanDecrypt(keybag)) |
| return false; |
| cryptographer->InstallKeys(keybag); |
| if (update_default) |
| cryptographer->SetDefaultKey(keybag.key_name()); |
| return true; |
| } |
| |
| void SyncEncryptionHandlerImpl::EnableEncryptEverythingImpl( |
| syncable::BaseTransaction* const trans) { |
| ModelTypeSet* encrypted_types = &UnlockVaultMutable(trans)->encrypted_types; |
| if (encrypt_everything_) { |
| DCHECK(encrypted_types->Equals(UserTypes())); |
| return; |
| } |
| encrypt_everything_ = true; |
| *encrypted_types = UserTypes(); |
| FOR_EACH_OBSERVER( |
| Observer, observers_, |
| OnEncryptedTypesChanged(*encrypted_types, encrypt_everything_)); |
| } |
| |
| bool SyncEncryptionHandlerImpl::DecryptPendingKeysWithKeystoreKey( |
| const std::string& keystore_key, |
| const sync_pb::EncryptedData& keystore_decryptor_token, |
| Cryptographer* cryptographer) { |
| DCHECK(cryptographer->has_pending_keys()); |
| if (keystore_decryptor_token.blob().empty()) |
| return false; |
| Cryptographer temp_cryptographer(cryptographer->encryptor()); |
| KeyParams keystore_params = {"localhost", "dummy", keystore_key_}; |
| if (temp_cryptographer.AddKey(keystore_params) && |
| temp_cryptographer.CanDecrypt(keystore_decryptor_token)) { |
| // Someone else migrated the nigori for us! How generous! Go ahead and |
| // install both the keystore key and the new default encryption key |
| // (i.e. the one provided by the keystore decryptor token) into the |
| // cryptographer. |
| // The keystore decryptor token is a keystore key encrypted blob containing |
| // the current serialized default encryption key (and as such should be |
| // able to decrypt the nigori node's encryption keybag). |
| DVLOG(1) << "Attempting to decrypt pending keys using " |
| << "keystore decryptor token."; |
| std::string serialized_nigori = |
| temp_cryptographer.DecryptToString(keystore_decryptor_token); |
| // This will decrypt the pending keys and add them if possible. The key |
| // within |serialized_nigori| will be the default after. |
| cryptographer->ImportNigoriKey(serialized_nigori); |
| // Theoretically the encryption keybag should already contain the keystore |
| // key. We explicitly add it as a safety measure. |
| cryptographer->AddNonDefaultKey(keystore_params); |
| if (cryptographer->is_ready()) { |
| std::string bootstrap_token; |
| cryptographer->GetBootstrapToken(&bootstrap_token); |
| DVLOG(1) << "Keystore decryptor token decrypted pending keys."; |
| FOR_EACH_OBSERVER( |
| SyncEncryptionHandler::Observer, |
| observers_, |
| OnBootstrapTokenUpdated(bootstrap_token, |
| PASSPHRASE_BOOTSTRAP_TOKEN)); |
| FOR_EACH_OBSERVER( |
| SyncEncryptionHandler::Observer, |
| observers_, |
| OnCryptographerStateChanged(cryptographer)); |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| } // namespace browser_sync |
