base for packet encryption

CMakeLists.txt

@@ -49,7 +49,6 @@ add_executable(M2-PT-DRP
         source/behavior/tasks/client/ClientTask.cpp
         source/behavior/tasks/client/ClientTask.hpp
         source/Context.hpp
-        source/utils/CacheMap.hpp
         source/packets/search/SearchPacketData.hpp
         source/packets/base/PacketContent.cpp
         source/packets/base/PacketContent.hpp

source/packets/base/Packet.cpp

@@ -1,6 +1,7 @@
 #include "Packet.hpp"
 
 #include <stdexcept>
+#include <cstring>
 
 #include "SecurityMode.hpp"
 
@@ -49,23 +50,50 @@ GenericPacketContent decryptPacketContentAes(const GenericPacket& packet) {
 */
 
 
-PacketContent Packet::getContent() const {
-    // TODO(Faraphel): implement RSA and AES
-    //   additional "context" argument to hold cryptographic keys ?
+inline Packet::Packet(
+        const Context& context,
+        const std::uint8_t channel,
+        SecurityMode securityMode,
+        const PacketContent& content
+) {
+    this->channel = channel;
+    this->securityMode = static_cast<std::uint8_t>(securityMode);
+
+    switch (securityMode) {
+        case SecurityMode::PLAIN:
+            this->content = static_cast<auto>(content);
+            break;
+        case SecurityMode::RSA:
+            this->content = encryptRsa(context, content);
+            break;
+        case SecurityMode::AES:
+            this->content = encryptAes(context, content);
+            break;
+        default:
+            throw std::invalid_argument("Invalid security mode.");
+    }
+}
+
+
+PacketContent Packet::getContent(
+    const Context& context,
+    const sockaddr_storage& address,
+    socklen_t addressLength
+) const {
+    PacketContent content {};
 
     switch (static_cast<SecurityMode>(this->securityMode)) {
         case SecurityMode::PLAIN:
-            return this->_content;
-
-        case SecurityMode::AES:
-            // return decryptPacketContentAes(packet);
-            throw std::runtime_error("Not implemented.");
-
+            std::memcpy(&content, &this->content, sizeof(PacketContent));
+            return content;
         case SecurityMode::RSA:
-            throw std::runtime_error("Not implemented.");
-
+            content = decryptRsa(context, this->content, address, addressLength);
+            return content;
+        case SecurityMode::AES:
+            content = decryptAes(context, this->content);
+            return content;
         default:
-            throw std::runtime_error("Unsupported security mode.");
+            throw std::invalid_argument("Invalid security mode.");
     }
 }
 

source/packets/base/Packet.hpp

@@ -3,7 +3,9 @@
 #include <array>
 #include <cstdint>
 
+#include "Context.hpp"
 #include "PacketContent.hpp"
+#include "SecurityMode.hpp"
 
 
 namespace drp::packet::base {
@@ -14,15 +16,26 @@ namespace drp::packet::base {
  * @param channel the channel of the packet. Two system can be created inside a same network by using different
  * channels value. "0" is used for "broadcast" message across networks.
  * @param securityMode the type of security used in the packet.
- * @param _content the content of the packet. It is encrypted accordingly to the securityMode.
+ * @param content the content of the packet. It is encrypted accordingly to the securityMode.
  */
-struct Packet {
+class Packet {
+public:
+    explicit Packet(
+        const Context& context,
+        std::uint8_t channel,
+        SecurityMode securityMode,
+        const PacketContent& content
+    );
+    [[nodiscard]] PacketContent getContent(
+        const Context& context,
+        const sockaddr_storage& address,
+        socklen_t addressLength
+    ) const;
+
+private:
     std::uint8_t channel;
     std::uint8_t securityMode;
-    PacketContent _content;
-
-    [[nodiscard]] PacketContent getContent() const;
-    void setContent(const PacketContent& content);
+    std::array<std::uint8_t, sizeof(PacketContent)> content;
 };
 
 

source/packets/base/PacketContent.cpp

@@ -1,7 +1,10 @@
 #include "PacketContent.hpp"
 
 #include <stdexcept>
+#include <openssl/pem.h>
+#include <openssl/x509.h>
 
+#include "Context.hpp"
 #include "Packet.hpp"
 #include "SecurityMode.hpp"
 
@@ -9,22 +12,34 @@
 namespace drp::packet::base {
 
 
-void Packet::setContent(const PacketContent &content) {
-    // TODO(Faraphel): implement RSA and AES
-    switch (static_cast<SecurityMode>(this->securityMode)) {
-        case SecurityMode::PLAIN:
-            this->_content = content;
-        return;
+void PacketContent::encryptRsa(const std::array<std::uint8_t, 2048>& publicKey) {
+    BIO* bioPublicKey = BIO_new_mem_buf(publicKey.data(), static_cast<int>(publicKey.size()));
+    EVP_PKEY* evpPublicKey = PEM_read_bio_PUBKEY(bioPublicKey, nullptr, nullptr, nullptr);
 
-        case SecurityMode::AES:
-            throw std::runtime_error("Not implemented.");
+    const std::unique_ptr<EVP_PKEY_CTX, decltype(&EVP_PKEY_CTX_free)> evpContext(
+        EVP_PKEY_CTX_new(evpPublicKey, nullptr),
+        EVP_PKEY_CTX_free
+    );
+    if (evpContext == nullptr)
+        throw std::runtime_error("Failed to create EVP_PKEY_CTX");
 
-        case SecurityMode::RSA:
-            throw std::runtime_error("Not implemented.");
+    if (EVP_PKEY_encrypt_init(evpContext.get()) <= 0)
+        throw std::runtime_error("Failed to initialize EVP_PKEY_CTX");
+
+    if (EVP_PKEY_CTX_set_rsa_padding(evpContext.get(), RSA_PKCS1_PADDING) <= 0)
+        throw std::runtime_error("Failed to set RSA_PKCS1_PADDING");
+
+    std::vector<std::uint8_t> cipher(EVP_PKEY_size(evpPublicKey));
+    std::size_t cipherLength;
+    EVP_PKEY_encrypt(
+        evpContext.get(),
+        cipher.data(),
+        &cipherLength,
+        this,
+        sizeof(*this)
+    );
+    cipher.resize(cipherLength);
 
-        default:
-            throw std::runtime_error("Unsupported security mode.");
-    }
 }
 
 

source/utils/CacheMap.hpp

@@ -1,35 +0,0 @@
-#pragma once
-#include <functional>
-#include <map>
-
-
-namespace drp::util {
-
-
-template<class Key, class Value, int limit, class Comparator = std::less<Value>>
-class CacheMap : std::map<Key, Value> {
-public:
-    void cache() {
-        // check if the limit have been reached.
-        if (this->size() <= limit)
-            return;
-
-        // apply the comparator on all the value to find the minimum.
-        auto minimum = this->begin();
-        for (const auto& it : this)
-            if (Comparator()(it.second, minimum))
-                minimum = it;
-
-        // delete this lowest value.
-        this->erase(minimum);
-    }
-
-    Value& operator[](const Key& key) {
-        const auto& value = std::map<Key, Value>::operator[](key);
-        this->cache();
-        return value;
-    }
-};
-
-
-}