1 files changed, 125 insertions, 0 deletions
diff --git a/src/encryption/Olm.h b/src/encryption/Olm.h
new file mode 100644
index 00000000..44e2b8ed
--- /dev/null
+++ b/src/encryption/Olm.h
@@ -0,0 +1,125 @@
+// SPDX-FileCopyrightText: 2021 Nheko Contributors
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#include <memory>
+#include <mtx/events.hpp>
+#include <mtx/events/encrypted.hpp>
+#include <mtxclient/crypto/client.hpp>
+
+#include <CacheCryptoStructs.h>
+
+constexpr auto OLM_ALGO = "m.olm.v1.curve25519-aes-sha2";
+
+namespace olm {
+Q_NAMESPACE
+
+enum DecryptionErrorCode
+{
+    NoError,
+    MissingSession, // Session was not found, retrieve from backup or request from other devices
+                    // and try again
+    MissingSessionIndex, // Session was found, but it does not reach back enough to this index,
+                         // retrieve from backup or request from other devices and try again
+    DbError,             // DB read failed
+    DecryptionFailed,    // libolm error
+    ParsingFailed,       // Failed to parse the actual event
+    ReplayAttack,        // Megolm index reused
+};
+Q_ENUM_NS(DecryptionErrorCode)
+
+struct DecryptionResult
+{
+    DecryptionErrorCode error;
+    std::optional<std::string> error_message;
+    std::optional<mtx::events::collections::TimelineEvents> event;
+};
+
+struct OlmMessage
+{
+    std::string sender_key;
+    std::string sender;
+
+    using RecipientKey = std::string;
+    std::map<RecipientKey, mtx::events::msg::OlmCipherContent> ciphertext;
+};
+
+void
+from_json(const nlohmann::json &obj, OlmMessage &msg);
+
+mtx::crypto::OlmClient *
+client();
+
+void
+handle_to_device_messages(const std::vector<mtx::events::collections::DeviceEvents> &msgs);
+
+nlohmann::json
+try_olm_decryption(const std::string &sender_key,
+                   const mtx::events::msg::OlmCipherContent &content);
+
+void
+handle_olm_message(const OlmMessage &msg, const UserKeyCache &otherUserDeviceKeys);
+
+//! Establish a new inbound megolm session with the decrypted payload from olm.
+void
+create_inbound_megolm_session(const mtx::events::DeviceEvent<mtx::events::msg::RoomKey> &roomKey,
+                              const std::string &sender_key,
+                              const std::string &sender_ed25519);
+void
+import_inbound_megolm_session(
+  const mtx::events::DeviceEvent<mtx::events::msg::ForwardedRoomKey> &roomKey);
+void
+lookup_keybackup(const std::string room, const std::string session_id);
+
+nlohmann::json
+handle_pre_key_olm_message(const std::string &sender,
+                           const std::string &sender_key,
+                           const mtx::events::msg::OlmCipherContent &content);
+
+mtx::events::msg::Encrypted
+encrypt_group_message(const std::string &room_id,
+                      const std::string &device_id,
+                      nlohmann::json body);
+
+//! Decrypt an event. Use dont_write_db to prevent db writes when already in a write transaction.
+DecryptionResult
+decryptEvent(const MegolmSessionIndex &index,
+             const mtx::events::EncryptedEvent<mtx::events::msg::Encrypted> &event,
+             bool dont_write_db = false);
+crypto::Trust
+calculate_trust(const std::string &user_id, const MegolmSessionIndex &index);
+
+void
+mark_keys_as_published();
+
+//! Request the encryption keys from sender's device for the given event.
+void
+send_key_request_for(mtx::events::EncryptedEvent<mtx::events::msg::Encrypted> e,
+                     const std::string &request_id,
+                     bool cancel = false);
+
+void
+handle_key_request_message(const mtx::events::DeviceEvent<mtx::events::msg::KeyRequest> &);
+
+void
+send_megolm_key_to_device(const std::string &user_id,
+                          const std::string &device_id,
+                          const mtx::events::msg::ForwardedRoomKey &payload);
+
+//! Send encrypted to device messages, targets is a map from userid to device ids or {} for all
+//! devices
+void
+send_encrypted_to_device_messages(const std::map<std::string, std::vector<std::string>> targets,
+                                  const mtx::events::collections::DeviceEvents &event,
+                                  bool force_new_session = false);
+
+//! Request backup and signing keys and cache them locally
+void
+request_cross_signing_keys();
+//! Download backup and signing keys and cache them locally
+void
+download_cross_signing_keys();
+
+} // namespace olm