2 files changed, 262 insertions, 0 deletions
diff --git a/lib/olm/qolmaccount.cpp b/lib/olm/qolmaccount.cpp
new file mode 100644
index 00000000..673f613b
--- /dev/null
+++ b/lib/olm/qolmaccount.cpp
@@ -0,0 +1,173 @@
+// SPDX-FileCopyrightText: 2021 Carl Schwan <carlschwan@kde.org>
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+
+#ifdef Quotient_E2EE_ENABLED
+#include "qolmaccount.h"
+#include <QJsonObject>
+#include <QJsonDocument>
+#include <QDebug>
+#include <iostream>
+
+QMap<QString, QString> OneTimeKeys::curve25519() const
+{
+    return keys[QStringLiteral("curve25519")];
+}
+
+std::optional<QMap<QString, QString>> OneTimeKeys::get(QString keyType) const
+{
+    if (!keys.contains(keyType)) {
+        return std::nullopt;
+    }
+    return keys[keyType];
+}
+
+// Convert PicklingMode to key
+QByteArray toKey(PicklingMode mode)
+{
+    if (std::holds_alternative<Unencrypted>(mode)) {
+        return "";
+    }
+    return std::get<Encrypted>(mode).key;
+}
+
+bool operator==(const IdentityKeys& lhs, const IdentityKeys& rhs)
+{
+    return lhs.curve25519 == rhs.curve25519 &&& lhs.ed25519 == rhs.ed25519;
+}
+
+// Conver olm error to enum
+QOlmAccount::OlmAccountError lastError(OlmAccount *account) {
+    const std::string error_raw = olm_account_last_error(account);
+
+    if (error_raw.compare("BAD_ACCOUNT_KEY")) {
+        return QOlmAccount::OlmAccountError::BadAccountKey;
+    } else if (error_raw.compare("BAD_MESSAGE_KEY_ID")) {
+        return QOlmAccount::OlmAccountError::BadMessageKeyId;
+    } else if (error_raw.compare("INVALID_BASE64")) {
+        return QOlmAccount::OlmAccountError::InvalidBase64;
+    } else if (error_raw.compare("NOT_ENOUGH_RANDOM")) {
+        return QOlmAccount::OlmAccountError::NotEnoughRandom;
+    } else if (error_raw.compare("OUTPUT_BUFFER_TOO_SMALL")) {
+        return QOlmAccount::OlmAccountError::OutputBufferTooSmall;
+    } else {
+        return QOlmAccount::OlmAccountError::Unknown;
+    }
+}
+
+QByteArray getRandom(size_t bufferSize)
+{
+    QByteArray buffer(bufferSize, '0');
+    std::generate(buffer.begin(), buffer.end(), std::rand);
+    return buffer;
+}
+
+QOlmAccount::QOlmAccount(OlmAccount *account)
+    : m_account(account)
+{}
+
+std::optional<QOlmAccount> QOlmAccount::create()
+{
+    auto account = olm_account(new uint8_t[olm_account_size()]);
+    size_t randomSize = olm_create_account_random_length(account);
+    QByteArray randomData = getRandom(randomSize);
+    const auto error = olm_create_account(account, randomData.data(), randomSize);
+    if (error == olm_error()) {
+        return std::nullopt;
+    }
+    return std::make_optional<QOlmAccount>(account);
+}
+
+std::variant<QOlmAccount, QOlmAccount::OlmAccountError> QOlmAccount::unpickle(QByteArray pickled, PicklingMode mode)
+{
+    auto account = olm_account(new uint8_t[olm_account_size()]);
+    const QByteArray key = toKey(mode);
+    const auto error = olm_unpickle_account(account, key.data(), key.length(), pickled.data(), pickled.size());
+    if (error == olm_error()) {
+        return lastError(account);
+    }
+    return QOlmAccount(account);
+}
+
+std::variant<QByteArray, QOlmAccount::OlmAccountError> QOlmAccount::pickle(PicklingMode mode)
+{
+    const QByteArray key = toKey(mode);
+    const size_t pickleLength = olm_pickle_account_length(m_account);
+    QByteArray pickleBuffer(pickleLength, '0');
+    const auto error = olm_pickle_account(m_account, key.data(),
+                key.length(), pickleBuffer.data(), pickleLength);
+    if (error == olm_error()) {
+        return lastError(m_account);
+    }
+    return pickleBuffer;
+}
+
+std::variant<IdentityKeys, QOlmAccount::OlmAccountError> QOlmAccount::identityKeys()
+{
+    const size_t keyLength = olm_account_identity_keys_length(m_account);
+    QByteArray keyBuffer(keyLength, '0');
+    const auto error = olm_account_identity_keys(m_account, keyBuffer.data(), keyLength);
+    if (error == olm_error()) {
+        return lastError(m_account);
+    }
+    const QJsonObject key = QJsonDocument::fromJson(keyBuffer).object();
+    return IdentityKeys {
+        key.value(QStringLiteral("curve25519")).toString().toUtf8(),
+        key.value(QStringLiteral("ed25519")).toString().toUtf8()
+    };
+}
+
+std::variant<QString, QOlmAccount::OlmAccountError> QOlmAccount::sign(QString message) const
+{
+    const size_t signatureLength = olm_account_signature_length(m_account);
+    QByteArray signatureBuffer(signatureLength, '0');
+    const auto error = olm_account_sign(m_account, message.data(), message.length(),
+            signatureBuffer.data(), signatureLength);
+
+    if (error == olm_error()) {
+        return lastError(m_account);
+    }
+    return QString::fromUtf8(signatureBuffer);
+}
+
+size_t QOlmAccount::maxNumberOfOneTimeKeys() const
+{
+    return olm_account_max_number_of_one_time_keys(m_account);
+}
+
+std::optional<QOlmAccount::OlmAccountError> QOlmAccount::generateOneTimeKeys(size_t numberOfKeys) const
+{
+    const size_t randomLen = olm_account_generate_one_time_keys_random_length(m_account, numberOfKeys);
+    QByteArray randomBuffer = getRandom(randomLen);
+    const auto error = olm_account_generate_one_time_keys(m_account, numberOfKeys, randomBuffer.data(), randomLen);
+
+    if (error == olm_error()) {
+        return lastError(m_account);
+    }
+    return std::nullopt;
+}
+
+std::variant<OneTimeKeys, QOlmAccount::OlmAccountError> QOlmAccount::oneTimeKeys() const
+{
+    const size_t oneTimeKeyLength = olm_account_one_time_keys_length(m_account);
+    QByteArray oneTimeKeysBuffer(oneTimeKeyLength, '0');
+
+    const auto error = olm_account_one_time_keys(m_account, oneTimeKeysBuffer.data(), oneTimeKeyLength);
+    if (error == olm_error()) {
+        return lastError(m_account);
+    }
+    const auto json = QJsonDocument::fromJson(oneTimeKeysBuffer).object();
+    OneTimeKeys oneTimeKeys;
+
+    for (const QJsonValue &key1 : json.keys()) {
+        auto oneTimeKeyObject = json[key1.toString()].toObject();
+        auto keyMap = QMap<QString, QString>();
+        for (const QString &key2 : oneTimeKeyObject.keys()) {
+            keyMap[key2] = oneTimeKeyObject[key2].toString();
+        }
+        oneTimeKeys.keys[key1.toString()] = keyMap;
+    }
+    return oneTimeKeys;
+}
+
+#endif
diff --git a/lib/olm/qolmaccount.h b/lib/olm/qolmaccount.h
new file mode 100644
index 00000000..219d7e48
--- /dev/null
+++ b/lib/olm/qolmaccount.h
@@ -0,0 +1,89 @@
+// SPDX-FileCopyrightText: 2021 Carl Schwan <carlschwan@kde.org>
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+#pragma once
+
+#include <QObject>
+#include <QMap>
+#include <optional>
+#include <string>
+#include <variant>
+#include "olm/olm.h"
+
+struct OlmAccount;
+
+struct Unencrypted {};
+struct Encrypted {
+    QByteArray key;
+};
+
+using PicklingMode = std::variant<Unencrypted, Encrypted>;
+
+template<class... Ts> struct overloaded : Ts... { using Ts::operator()...; };
+template<class... Ts> overloaded(Ts...) -> overloaded<Ts...>;
+
+struct IdentityKeys
+{
+    QByteArray curve25519;
+    QByteArray ed25519;
+};
+
+//! Struct representing the the one-time keys.
+struct OneTimeKeys
+{
+    QMap<QString, QMap<QString, QString>> keys;
+
+    //! Get the HashMap containing the curve25519 one-time keys.
+    QMap<QString, QString> curve25519() const;
+
+    //! Get a reference to the hashmap corresponding to given key type.
+    std::optional<QMap<QString, QString>> get(QString keyType) const;
+};
+
+bool operator==(const IdentityKeys& lhs, const IdentityKeys& rhs);
+
+//! An olm account manages all cryptographic keys used on a device.
+//! \code{.cpp}
+//! const auto olmAccount = new QOlmAccount(this);
+//! \endcode
+class QOlmAccount
+{
+public:
+    enum OlmAccountError {
+        BadAccountKey,
+        BadMessageKeyId,
+        InvalidBase64,
+        NotEnoughRandom,
+        OutputBufferTooSmall,
+        Unknown,
+    };
+
+    //! Creates a new instance of OlmAccount. During the instantiation
+    //! the Ed25519 fingerprint key pair and the Curve25519 identity key
+    //! pair are generated. For more information see <a
+    //! href="https://matrix.org/docs/guides/e2e_implementation.html#keys-used-in-end-to-end-encryption">here</a>.
+    static std::optional<QOlmAccount> create();
+    static std::variant<QOlmAccount, OlmAccountError> unpickle(QByteArray picked, PicklingMode mode);
+
+    //! Serialises an OlmAccount to encrypted Base64.
+    std::variant<QByteArray, OlmAccountError> pickle(PicklingMode mode);
+    std::variant<IdentityKeys, OlmAccountError> identityKeys();
+
+    //! Returns the signature of the supplied message.
+    std::variant<QString, OlmAccountError> sign(QString message) const;
+
+    //! Maximum number of one time keys that this OlmAccount can
+    //! currently hold.
+    size_t maxNumberOfOneTimeKeys() const;
+
+    //! Generates the supplied number of one time keys.
+    std::optional<OlmAccountError> generateOneTimeKeys(size_t numberOfKeys) const;
+
+    //! Gets the OlmAccount's one time keys formatted as JSON.
+    std::variant<OneTimeKeys, OlmAccountError> oneTimeKeys() const;
+
+    // HACK do not use directly
+    QOlmAccount(OlmAccount *account);
+private:
+    OlmAccount *m_account;
+};