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#include "encryptionmanager.h"
#include "connection.h"
#include "csapi/keys.h"
#include <QtCore/QHash>
#include <QtCore/QStringBuilder>
#include <account.h> // QtOlm
#include <functional>
#include <memory>
using namespace QMatrixClient;
using namespace QtOlm;
using std::move;
static const auto ed25519Name = QStringLiteral("ed25519");
static const auto Curve25519Name = QStringLiteral("curve25519");
static const auto SignedCurve25519Name = QStringLiteral("signed_curve25519");
static const auto OlmV1Curve25519AesSha2AlgoName =
QStringLiteral("m.olm.v1.curve25519-aes-sha2");
static const auto MegolmV1AesSha2AlgoName =
QStringLiteral("m.megolm.v1.aes-sha2");
static const QStringList SupportedAlgorithms = { OlmV1Curve25519AesSha2AlgoName,
MegolmV1AesSha2AlgoName };
class EncryptionManager::Private
{
public:
explicit Private(const QByteArray& encryptionAccountPickle,
float signedKeysProportion, float oneTimeKeyThreshold)
: signedKeysProportion(move(signedKeysProportion))
, oneTimeKeyThreshold(move(oneTimeKeyThreshold))
{
Q_ASSERT((0 <= signedKeysProportion) && (signedKeysProportion <= 1));
Q_ASSERT((0 <= oneTimeKeyThreshold) && (oneTimeKeyThreshold <= 1));
if (encryptionAccountPickle.isEmpty()) {
olmAccount.reset(new Account());
} else {
olmAccount.reset(
new Account(encryptionAccountPickle)); // TODO: passphrase even
// with qtkeychain?
}
/*
* Note about targetKeysNumber:
*
* From: https://github.com/Zil0/matrix-python-sdk/
* File: matrix_client/crypto/olm_device.py
*
* Try to maintain half the number of one-time keys libolm can hold
* uploaded on the HS. This is because some keys will be claimed by
* peers but not used instantly, and we want them to stay in libolm,
* until the limit is reached and it starts discarding keys, starting by
* the oldest.
*/
targetKeysNumber = olmAccount->maxOneTimeKeys(); // 2 // see note below
targetOneTimeKeyCounts = {
{ SignedCurve25519Name,
qRound(signedKeysProportion * targetKeysNumber) },
{ Curve25519Name,
qRound((1 - signedKeysProportion) * targetKeysNumber) }
};
}
~Private() = default;
UploadKeysJob* uploadIdentityKeysJob = nullptr;
UploadKeysJob* uploadOneTimeKeysJob = nullptr;
QScopedPointer<Account> olmAccount;
float signedKeysProportion;
float oneTimeKeyThreshold;
int targetKeysNumber;
void updateKeysToUpload();
bool oneTimeKeyShouldUpload();
QHash<QString, int> oneTimeKeyCounts;
void setOneTimeKeyCounts(const QHash<QString, int> oneTimeKeyCountsNewValue)
{
oneTimeKeyCounts = oneTimeKeyCountsNewValue;
updateKeysToUpload();
}
QHash<QString, int> oneTimeKeysToUploadCounts;
QHash<QString, int> targetOneTimeKeyCounts;
};
EncryptionManager::EncryptionManager(const QByteArray& encryptionAccountPickle,
float signedKeysProportion,
float oneTimeKeyThreshold, QObject* parent)
: QObject(parent)
, d(std::make_unique<Private>(std::move(encryptionAccountPickle),
std::move(signedKeysProportion),
std::move(oneTimeKeyThreshold)))
{}
EncryptionManager::~EncryptionManager() = default;
void EncryptionManager::uploadIdentityKeys(Connection* connection)
{
// https://matrix.org/docs/spec/client_server/latest#post-matrix-client-r0-keys-upload
DeviceKeys deviceKeys {
/*
* The ID of the user the device belongs to. Must match the user ID used
* when logging in. The ID of the device these keys belong to. Must
* match the device ID used when logging in. The encryption algorithms
* supported by this device.
*/
connection->userId(),
connection->deviceId(),
SupportedAlgorithms,
/*
* Public identity keys. The names of the properties should be in the
* format <algorithm>:<device_id>. The keys themselves should be encoded
* as specified by the key algorithm.
*/
{ { Curve25519Name + QStringLiteral(":") + connection->deviceId(),
d->olmAccount->curve25519IdentityKey() },
{ ed25519Name + QStringLiteral(":") + connection->deviceId(),
d->olmAccount->ed25519IdentityKey() } },
/* signatures should be provided after the unsigned deviceKeys
generation */
{}
};
QJsonObject deviceKeysJsonObject = toJson(deviceKeys);
/* additionally removing signatures key,
* since we could not initialize deviceKeys
* without an empty signatures value:
*/
deviceKeysJsonObject.remove(QStringLiteral("signatures"));
/*
* Signatures for the device key object.
* A map from user ID, to a map from <algorithm>:<device_id> to the
* signature. The signature is calculated using the process called Signing
* JSON.
*/
deviceKeys.signatures = {
{ connection->userId(),
{ { ed25519Name + QStringLiteral(":") + connection->deviceId(),
d->olmAccount->sign(deviceKeysJsonObject) } } }
};
connect(d->uploadIdentityKeysJob, &BaseJob::success, this, [this] {
d->setOneTimeKeyCounts(d->uploadIdentityKeysJob->oneTimeKeyCounts());
qDebug() << QString("Uploaded identity keys.");
});
d->uploadIdentityKeysJob = connection->callApi<UploadKeysJob>(deviceKeys);
}
void EncryptionManager::uploadOneTimeKeys(Connection* connection,
bool forceUpdate)
{
if (forceUpdate || d->oneTimeKeyCounts.isEmpty()) {
auto job = connection->callApi<UploadKeysJob>();
connect(job, &BaseJob::success, this, [job, this] {
d->setOneTimeKeyCounts(job->oneTimeKeyCounts());
});
}
int signedKeysToUploadCount =
d->oneTimeKeysToUploadCounts.value(SignedCurve25519Name, 0);
int unsignedKeysToUploadCount =
d->oneTimeKeysToUploadCounts.value(Curve25519Name, 0);
d->olmAccount->generateOneTimeKeys(signedKeysToUploadCount
+ unsignedKeysToUploadCount);
QHash<QString, QVariant> oneTimeKeys = {};
const auto& olmAccountCurve25519OneTimeKeys =
d->olmAccount->curve25519OneTimeKeys();
int oneTimeKeysCounter = 0;
for (auto it = olmAccountCurve25519OneTimeKeys.cbegin();
it != olmAccountCurve25519OneTimeKeys.cend(); ++it) {
QString keyId = it.key();
QString keyType;
QVariant key;
if (oneTimeKeysCounter < signedKeysToUploadCount) {
QJsonObject message { { QStringLiteral("key"),
it.value().toString() } };
key = d->olmAccount->sign(message);
keyType = SignedCurve25519Name;
} else {
key = it.value();
keyType = Curve25519Name;
}
++oneTimeKeysCounter;
oneTimeKeys.insert(QString("%1:%2").arg(keyType).arg(keyId), key);
}
d->uploadOneTimeKeysJob = connection->callApi<UploadKeysJob>(none,
oneTimeKeys);
d->olmAccount->markKeysAsPublished();
qDebug() << QString("Uploaded new one-time keys: %1 signed, %2 unsigned.")
.arg(signedKeysToUploadCount)
.arg(unsignedKeysToUploadCount);
}
QByteArray EncryptionManager::olmAccountPickle()
{
return d->olmAccount->pickle(); // TODO: passphrase even with qtkeychain?
}
void EncryptionManager::Private::updateKeysToUpload()
{
for (auto it = targetOneTimeKeyCounts.cbegin();
it != targetOneTimeKeyCounts.cend(); ++it) {
int numKeys = oneTimeKeyCounts.value(it.key(), 0);
int numToCreate = qMax(it.value() - numKeys, 0);
oneTimeKeysToUploadCounts.insert(it.key(), numToCreate);
}
}
bool EncryptionManager::Private::oneTimeKeyShouldUpload()
{
if (oneTimeKeyCounts.empty())
return true;
for (auto it = targetOneTimeKeyCounts.cbegin();
it != targetOneTimeKeyCounts.cend(); ++it) {
if (oneTimeKeyCounts.value(it.key(), 0)
< it.value() * oneTimeKeyThreshold)
return true;
}
return false;
}
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