added ip banning

Makefile

@@ -10,7 +10,7 @@ BUILD_DIR = build
 SOURCES_CLIENT = client.cpp
 OBJS_CLIENT = $(addprefix $(BUILD_DIR)/,$(SOURCES_CLIENT:.cpp=.o))
 
-SOURCES_SERVER = server.cpp user.cpp user_handler.cpp mail.cpp
+SOURCES_SERVER = server.cpp user.cpp user_handler.cpp mail.cpp ip_ban.cpp
 OBJS_SERVER = $(addprefix $(BUILD_DIR)/,$(SOURCES_SERVER:.cpp=.o))
 
 all: $(BUILD_DIR) $(TARGET)

server/ip_ban.cpp

@@ -0,0 +1,54 @@
+#include "ip_ban.h"
+
+#include <chrono>
+#include <filesystem>
+#include <iterator>
+#include <fstream>
+
+ip_ban::ip_ban() : m_ban()
+{
+	this->file = fs::path();
+}
+
+ip_ban::~ip_ban()
+{
+	if (this->file.empty())
+		return;
+	
+	json jsonfile = this->ban_list;
+
+	std::ofstream ofs(this->file, std::ofstream::out | std::ofstream::trunc);
+	ofs << jsonfile.dump();
+}
+
+void ip_ban::loadFile(fs::path file)
+{
+	this->file = file;
+
+	if (fs::exists(file)) {
+		std::ifstream ifs(file);
+		this->ban_list = json::parse(ifs);
+	}
+}
+
+void ip_ban::failedAttempt(std::string username, std::string ip)
+{
+	printf("%s\n", username.c_str());
+	std::unique_lock<std::shared_mutex> lock(this->m_ban);
+
+	std::map<std::string, std::pair<std::map<std::string, ushort>, time_t>>::iterator it = this->ban_list.insert({ip, {{}, 0}}).first;
+	if (++it->second.first.insert({username, 0}).first->second >= MAX_ATTEMPTS) { // increase attempt count && check if reached MAX_ATTEMPTS
+		for (auto& pair : it->second.first ) { // reset attempts to 0 for all names
+			pair.second = 0;
+		}
+		(*it).second.second = std::chrono::system_clock::to_time_t(std::chrono::system_clock::now()) + BAN_TIME; // set unban time to current time + BAN_TIME seconds
+	}
+}
+
+bool ip_ban::checkBanned(std::string ip)
+{
+	std::shared_lock<std::shared_mutex> lock(this->m_ban);
+
+	std::map<std::string, std::pair<std::map<std::string, ushort>, time_t>>::iterator it;
+	return (it = this->ban_list.find(ip)) != this->ban_list.end() && (*it).second.second > std::chrono::system_clock::to_time_t(std::chrono::system_clock::now());
+}

server/ip_ban.h

@@ -0,0 +1,47 @@
+#pragma once
+
+#include <filesystem>
+#include <map>
+#include <mutex>
+#include <shared_mutex>
+#include <string>
+#include <chrono>
+
+#include <nlohmann/json.hpp>
+
+#define BAN_TIME 60
+#define MAX_ATTEMPTS 3
+
+namespace fs = std::filesystem;
+
+using json = nlohmann::json;
+
+class ip_ban {
+public:
+
+	static ip_ban& getInstance() {
+		static ip_ban instance;
+		return instance;
+	};
+
+	ip_ban(ip_ban const&) = delete;
+	ip_ban(ip_ban&&) = delete;
+	ip_ban& operator=(ip_ban const&) = delete;
+	ip_ban& operator=(ip_ban &&) = delete;
+
+	void loadFile(fs::path file);
+
+	void failedAttempt(std::string username, std::string ip);
+	bool checkBanned(std::string ip);
+
+protected:
+
+	ip_ban();
+	~ip_ban();
+
+	std::shared_mutex m_ban;
+
+	fs::path file;
+	std::map<std::string, std::pair<std::map<std::string, ushort>, time_t>> ban_list;
+	
+};

server/mail.cpp

@@ -1,5 +1,4 @@
 #include "mail.h"
-#include <mutex>
 
 mail::mail(std::string filename, std::string subject, std::string sender) :
 	filename(filename),

server/server.cpp

@@ -1,3 +1,4 @@
+#include "ip_ban.h"
 #include "user.h"
 #include "user_handler.h"
 
@@ -71,7 +72,7 @@ std::string getSha1(const std::string& p_arg);
 void *clientCommunication(void *data);
 void signalHandler(int sig);
 
-std::string cmdLOGIN(std::vector<std::string>& received, std::string& loggedInUsername);
+std::string cmdLOGIN(std::vector<std::string>& received, std::string& loggedInUsername, const std::string& ip);
 std::string cmdSEND(std::vector<std::string>& received, const std::string& loggedInUsername);
 std::string cmdLIST(std::vector<std::string>& received, const std::string& loggedInUsername);
 std::string cmdREAD(std::vector<std::string>& received, const std::string& loggedInUsername);
@@ -81,6 +82,13 @@ std::string cmdDEL(std::vector<std::string>& received, const std::string& logged
 inline void exiting();
 inline std::string read_file(std::string_view path);
 
+struct args
+{
+    int socket;
+    std::string ip;
+    fs::path spool_dir;
+};
+
 int main (int argc, char* argv[])
 {
 	if (argc < 3 ||	
@@ -106,6 +114,8 @@ int main (int argc, char* argv[])
 
 	user_handler::getInstance().setSpoolDir(spool_dir);
 
+	ip_ban::getInstance().loadFile(spool_dir / "bans.json");
+
 	std::atexit(exiting);
 
 	char* p;
@@ -181,7 +191,7 @@ int main (int argc, char* argv[])
 				 ntohs(cliaddress.sin_port));
 		// clientCommunication(&new_socket); // returnValue can be ignored
 		pthread_t tid;
-		pthread_create(&tid, NULL, clientCommunication, (void *)new int(new_socket));
+		pthread_create(&tid, NULL, clientCommunication, static_cast<void *>(new args{new_socket, inet_ntoa(cliaddress.sin_addr), spool_dir}));
 		threads.push_back(tid);
 		new_socket = -1;
 	}
@@ -219,9 +229,12 @@ void printUsage()
 
 void *clientCommunication(void *data)
 {
+	args* args = (struct args*) data;
+
 	char buffer[BUF];
 	int size;
-	int *current_socket = (int *)data;
+	int *current_socket = &args->socket;
+	std::string ip = args->ip;
 
 	std::string incomplete_message = "";
 
@@ -275,7 +288,7 @@ void *clientCommunication(void *data)
 
 		switch (cmd) {
 		case LOGIN:
-			response = cmdLOGIN(lines, loggedInUsername);
+			response = cmdLOGIN(lines, loggedInUsername, ip);
 			break;
 		case SEND:
 			if (lines.size() < 5 || lines.back().compare(".") != 0) {
@@ -320,7 +333,7 @@ void *clientCommunication(void *data)
 		*current_socket = -1;
 	}
 
-	delete(current_socket);
+	delete(args);
 	return NULL;
 }
 
@@ -394,7 +407,7 @@ inline void exiting()
 	printf("Saving...	\n");
 }
 
-std::string cmdLOGIN(std::vector<std::string>& received, std::string& loggedInUsername)
+std::string cmdLOGIN(std::vector<std::string>& received, std::string& loggedInUsername, const std::string& ip)
 {
 	if (received.size() < 3) {
         return "ERR\n";
@@ -428,10 +441,16 @@ std::string cmdLOGIN(std::vector<std::string>& received, std::string& loggedInUs
     bindCredentials.bv_len = ldapBindPassword.length();
     rc = ldap_sasl_bind_s(ldapHandle, ldapBindUser.c_str(), LDAP_SASL_SIMPLE, &bindCredentials, NULL, NULL, NULL);
     if (rc != LDAP_SUCCESS) {
+    	ip_ban::getInstance().failedAttempt(received.at(1), ip);
         ldap_unbind_ext_s(ldapHandle, NULL, NULL);
         return "ERR\n";
     }
 
+    if (ip_ban::getInstance().checkBanned(ip)) {
+		ldap_unbind_ext_s(ldapHandle, NULL, NULL);
+		return "ERR\n";
+    }
+
     loggedInUsername = received.at(1);
 	ldap_unbind_ext_s(ldapHandle, NULL, NULL);