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#pragma once
#include <boost/optional.hpp>
#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 {
enum class DecryptionErrorCode
{
MissingSession, // Session was not found, 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
UnknownFingerprint, // Unknown device Fingerprint
};
struct DecryptionResult
{
std::optional<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;
};
inline void
from_json(const nlohmann::json &obj, OlmMessage &msg)
{
if (obj.at("type") != "m.room.encrypted")
throw std::invalid_argument("invalid type for olm message");
if (obj.at("content").at("algorithm") != OLM_ALGO)
throw std::invalid_argument("invalid algorithm for olm message");
msg.sender = obj.at("sender");
msg.sender_key = obj.at("content").at("sender_key");
msg.ciphertext = obj.at("content")
.at("ciphertext")
.get<std::map<std::string, mtx::events::msg::OlmCipherContent>>();
}
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);
//! 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);
void
import_inbound_megolm_session(
const mtx::events::DeviceEvent<mtx::events::msg::ForwardedRoomKey> &roomKey);
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);
DecryptionResult
decryptEvent(const MegolmSessionIndex &index,
const mtx::events::EncryptedEvent<mtx::events::msg::Encrypted> &event);
void
mark_keys_as_published();
//! Request the encryption keys from sender's device for the given event.
void
request_keys(const std::string &room_id, const std::string &event_id);
void
send_key_request_for(const std::string &room_id,
const mtx::events::EncryptedEvent<mtx::events::msg::Encrypted> &);
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);
} // namespace olm
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