feat: Implement secure credential management with AES encryption

backend/build.gradle.kts

@@ -8,7 +8,7 @@ plugins {
 
 val mapStructVersion = "1.6.3"
 val swaggerOpenAPIVersion = "3.0.3"
-val dotEnvVersion = "5.1.0"
+val bouncyCastleVersion = "1.84"
 
 group = "com.devaulty"
 version = "0.0.1-SNAPSHOT"
@@ -35,10 +35,9 @@ dependencies {
 	implementation("org.springframework.security:spring-security-crypto")
 	implementation("org.mapstruct:mapstruct:${mapStructVersion}")
 	implementation("org.springdoc:springdoc-openapi-starter-webmvc-ui:${swaggerOpenAPIVersion}")
-	implementation(platform("me.paulschwarz:spring-dotenv-bom:${dotEnvVersion}"))
+	implementation("org.bouncycastle:bcprov-jdk18on:${bouncyCastleVersion}")
 
 	developmentOnly("org.springframework.boot:spring-boot-devtools")
-	developmentOnly("me.paulschwarz:springboot4-dotenv:${dotEnvVersion}")
 
 	runtimeOnly("org.xerial:sqlite-jdbc")
 	runtimeOnly("org.hibernate.orm:hibernate-community-dialects")
@@ -50,6 +49,7 @@ dependencies {
 	testImplementation("org.springframework.boot:spring-boot-starter-liquibase-test")
 	testImplementation("org.springframework.boot:spring-boot-starter-validation-test")
 	testImplementation("org.springframework.boot:spring-boot-starter-webmvc-test")
+
 	testRuntimeOnly("org.junit.platform:junit-platform-launcher")
 }
 

backend/src/main/java/com/devaulty/backend/BackendApplication.java

@@ -3,10 +3,12 @@
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.data.web.config.EnableSpringDataWebSupport;
+import org.springframework.scheduling.annotation.EnableScheduling;
 
 import static org.springframework.data.web.config.EnableSpringDataWebSupport.PageSerializationMode.VIA_DTO;
 
 @SpringBootApplication
+@EnableScheduling
 @EnableSpringDataWebSupport(pageSerializationMode = VIA_DTO)
 public class BackendApplication {
 

backend/src/main/java/com/devaulty/backend/adapter/in/scheduler/VaultAutoLockScheduler.java

@@ -0,0 +1,34 @@
+package com.devaulty.backend.adapter.in.scheduler;
+
+import com.devaulty.backend.application.port.out.security.MasterKeySessionPort;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Component;
+
+import java.time.Duration;
+
+@Component
+public class VaultAutoLockScheduler {
+
+    private final Duration inactivityTimeout = Duration.ofMinutes(15);
+
+    private static final Logger logger = LoggerFactory.getLogger(VaultAutoLockScheduler.class);
+
+    private final MasterKeySessionPort masterKeySessionPort;
+
+    public VaultAutoLockScheduler(MasterKeySessionPort masterKeySessionPort) {
+        this.masterKeySessionPort = masterKeySessionPort;
+    }
+
+    @Scheduled(fixedDelay = 10000) // Runs every 10 seconds
+    public void purgeExpiredSession() {
+        if (!masterKeySessionPort.hasKey()) {
+            return;
+        }
+
+        if (masterKeySessionPort.getOrClearIfExpired(inactivityTimeout) == null) {
+            logger.info("Inactivity Timeout reached. Vault locked.");
+        }
+    }
+}