6 files changed, 52 insertions, 2 deletions
diff --git a/lib/events/encryptedevent.cpp b/lib/events/encryptedevent.cpp
index 9d07a35f..c97ccc16 100644
--- a/lib/events/encryptedevent.cpp
+++ b/lib/events/encryptedevent.cpp
@@ -61,3 +61,10 @@ RoomEventPtr EncryptedEvent::createDecrypted(const QString &decrypted) const
     }
     return loadEvent<RoomEvent>(eventObject);
 }
+
+void EncryptedEvent::setRelation(const QJsonObject& relation)
+{
+    auto content = contentJson();
+    content["m.relates_to"] = relation;
+    editJson()["content"] = content;
+}
diff --git a/lib/events/encryptedevent.h b/lib/events/encryptedevent.h
index 72efffd4..ddd5e415 100644
--- a/lib/events/encryptedevent.h
+++ b/lib/events/encryptedevent.h
@@ -56,6 +56,8 @@ public:
     QString deviceId() const { return contentPart<QString>(DeviceIdKeyL); }
     QString sessionId() const { return contentPart<QString>(SessionIdKeyL); }
     RoomEventPtr createDecrypted(const QString &decrypted) const;
+
+    void setRelation(const QJsonObject& relation);
 };
 REGISTER_EVENT_TYPE(EncryptedEvent)
 
diff --git a/lib/events/encryptedfile.cpp b/lib/events/encryptedfile.cpp
index d4a517bd..d35ee28f 100644
--- a/lib/events/encryptedfile.cpp
+++ b/lib/events/encryptedfile.cpp
@@ -8,6 +8,7 @@
 #ifdef Quotient_E2EE_ENABLED
 #include <openssl/evp.h>
 #include <QtCore/QCryptographicHash>
+#include "e2ee/qolmutils.h"
 #endif
 
 using namespace Quotient;
@@ -27,7 +28,7 @@ QByteArray EncryptedFile::decryptFile(const QByteArray& ciphertext) const
     {
         int length;
         auto* ctx = EVP_CIPHER_CTX_new();
-        QByteArray plaintext(ciphertext.size() + EVP_CIPHER_CTX_block_size(ctx)
+        QByteArray plaintext(ciphertext.size() + EVP_MAX_BLOCK_LENGTH
                                  - 1,
                              '\0');
         EVP_DecryptInit_ex(ctx, EVP_aes_256_ctr(), nullptr,
@@ -44,7 +45,7 @@ QByteArray EncryptedFile::decryptFile(const QByteArray& ciphertext) const
                                 + length,
                             &length);
         EVP_CIPHER_CTX_free(ctx);
-        return plaintext;
+        return plaintext.left(ciphertext.size());
     }
 #else
     qWarning(MAIN) << "This build of libQuotient doesn't support E2EE, "
@@ -53,6 +54,31 @@ QByteArray EncryptedFile::decryptFile(const QByteArray& ciphertext) const
 #endif
 }
 
+std::pair<EncryptedFile, QByteArray> EncryptedFile::encryptFile(const QByteArray &plainText)
+{
+#ifdef Quotient_E2EE_ENABLED
+    QByteArray k = getRandom(32);
+    auto kBase64 = k.toBase64();
+    QByteArray iv = getRandom(16);
+    JWK key = {"oct"_ls, {"encrypt"_ls, "decrypt"_ls}, "A256CTR"_ls, QString(k.toBase64()).replace(u'/', u'_').replace(u'+', u'-').left(kBase64.indexOf('=')), true};
+
+    int length;
+    auto* ctx = EVP_CIPHER_CTX_new();
+    QByteArray cipherText(plainText.size(), plainText.size() + EVP_MAX_BLOCK_LENGTH - 1);
+    EVP_EncryptInit_ex(ctx, EVP_aes_256_ctr(), nullptr, reinterpret_cast<const unsigned char*>(k.data()),reinterpret_cast<const unsigned char*>(iv.data()));
+    EVP_EncryptUpdate(ctx, reinterpret_cast<unsigned char*>(cipherText.data()), &length, reinterpret_cast<const unsigned char*>(plainText.data()), plainText.size());
+    EVP_EncryptFinal_ex(ctx, reinterpret_cast<unsigned char*>(cipherText.data()) + length, &length);
+    EVP_CIPHER_CTX_free(ctx);
+
+    auto hash = QCryptographicHash::hash(cipherText, QCryptographicHash::Sha256).toBase64();
+    auto ivBase64 = iv.toBase64();
+    EncryptedFile file = {{}, key, ivBase64.left(ivBase64.indexOf('=')), {{QStringLiteral("sha256"), hash.left(hash.indexOf('='))}}, "v2"_ls};
+    return {file, cipherText};
+#else
+    return {};
+#endif
+}
+
 void JsonObjectConverter<EncryptedFile>::dumpTo(QJsonObject& jo,
                                                 const EncryptedFile& pod)
 {
diff --git a/lib/events/encryptedfile.h b/lib/events/encryptedfile.h
index d0c4a030..022ac91e 100644
--- a/lib/events/encryptedfile.h
+++ b/lib/events/encryptedfile.h
@@ -46,6 +46,7 @@ public:
     QString v;
 
     QByteArray decryptFile(const QByteArray &ciphertext) const;
+    static std::pair<EncryptedFile, QByteArray> encryptFile(const QByteArray& plainText);
 };
 
 template <>
diff --git a/lib/events/roomkeyevent.cpp b/lib/events/roomkeyevent.cpp
index 332be3f7..68962950 100644
--- a/lib/events/roomkeyevent.cpp
+++ b/lib/events/roomkeyevent.cpp
@@ -10,3 +10,16 @@ RoomKeyEvent::RoomKeyEvent(const QJsonObject &obj) : Event(typeId(), obj)
     if (roomId().isEmpty())
         qCWarning(E2EE) << "Room key event has empty room id";
 }
+
+RoomKeyEvent::RoomKeyEvent(const QString& algorithm, const QString& roomId, const QString& sessionId, const QString& sessionKey, const QString& senderId)
+    : Event(typeId(), {
+        {"content", QJsonObject{
+            {"algorithm", algorithm},
+            {"room_id", roomId},
+            {"session_id", sessionId},
+            {"session_key", sessionKey},
+        }},
+        {"sender", senderId},
+        {"type", "m.room_key"},
+    })
+{}
diff --git a/lib/events/roomkeyevent.h b/lib/events/roomkeyevent.h
index ed4c9440..2bda3086 100644
--- a/lib/events/roomkeyevent.h
+++ b/lib/events/roomkeyevent.h
@@ -12,6 +12,7 @@ public:
     DEFINE_EVENT_TYPEID("m.room_key", RoomKeyEvent)
 
     explicit RoomKeyEvent(const QJsonObject& obj);
+    explicit RoomKeyEvent(const QString& algorithm, const QString& roomId, const QString &sessionId, const QString& sessionKey, const QString& senderId);
 
     QString algorithm() const { return contentPart<QString>("algorithm"_ls); }
     QString roomId() const { return contentPart<QString>(RoomIdKeyL); }