add newTokenIsDifferent test

src/main/java/com/ddf/vodsystem/VodSystemApplication.java

@@ -1,13 +1,16 @@
 package com.ddf.vodsystem;
 
+import com.ddf.vodsystem.dto.properties.AuthProperties;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.scheduling.annotation.EnableAsync;
 import org.springframework.scheduling.annotation.EnableScheduling;
 
 @SpringBootApplication
 @EnableScheduling
 @EnableAsync
+@EnableConfigurationProperties(AuthProperties.class)
 public class VodSystemApplication {
 
 	/**

src/main/java/com/ddf/vodsystem/configuration/TimeConfig.java

@@ -0,0 +1,15 @@
+package com.ddf.vodsystem.configuration;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import java.time.Clock;
+
+@Configuration
+public class TimeConfig {
+
+    @Bean
+    public Clock clock() {
+        return Clock.systemUTC();
+    }
+}

src/main/java/com/ddf/vodsystem/controllers/UserController.java

@@ -2,6 +2,7 @@ package com.ddf.vodsystem.controllers;
 
 import com.ddf.vodsystem.dto.APIResponse;
 import com.ddf.vodsystem.controllers.dto.Token;
+import com.ddf.vodsystem.dto.TokenPackage;
 import com.ddf.vodsystem.entities.User;
 import com.ddf.vodsystem.exceptions.NotAuthenticated;
 import com.ddf.vodsystem.services.UserService;
@@ -19,7 +20,7 @@ import java.util.Optional;
 public class UserController {
     private final UserService userService;
 
-    @Value("${jwt.expiration}")
+    @Value("${app.security.expiration.jwt}")
     private long jwtExpiration;
     private static final String SUCCESS = "success";
 
@@ -58,12 +59,12 @@ public class UserController {
      * @return {@code 200 OK} wrapping the issued JWT as a {@link Token}
      */
     @PostMapping("/login")
-    public ResponseEntity<APIResponse<Token>> login(@RequestBody Token token,
+    public ResponseEntity<APIResponse<TokenPackage>> login(@RequestBody Token token,
                                                            HttpServletRequest request,
                                                            HttpServletResponse response) {
-        String jwt = userService.login(token.token());
+        TokenPackage tokenPackage = userService.login(token.token());
 
-        ResponseCookie cookie = ResponseCookie.from("token", jwt)
+        ResponseCookie cookie = ResponseCookie.from("token", tokenPackage.accessToken())
                 .httpOnly(true)
                 .maxAge(jwtExpiration / 1000)
                 .sameSite(request.isSecure() ? "None" : "Lax")
@@ -74,7 +75,7 @@ public class UserController {
         response.addHeader("Set-Cookie", cookie.toString());
 
         return ResponseEntity.ok(
-                new APIResponse<>(SUCCESS, "Logged in successfully", new Token(jwt))
+                new APIResponse<>(SUCCESS, "Logged in successfully", tokenPackage)
         );
     }
 

src/main/java/com/ddf/vodsystem/dto/GoogleUser.java

@@ -0,0 +1,9 @@
+package com.ddf.vodsystem.dto;
+
+public record GoogleUser(
+        String googleId,
+        String email,
+        String name,
+        String profilePictureUrl
+) {
+}

src/main/java/com/ddf/vodsystem/dto/TokenPackage.java

@@ -0,0 +1,7 @@
+package com.ddf.vodsystem.dto;
+
+public record TokenPackage (
+        String refreshToken,
+        String accessToken
+) {
+}

src/main/java/com/ddf/vodsystem/dto/properties/AuthProperties.java

@@ -0,0 +1,32 @@
+package com.ddf.vodsystem.dto.properties;
+
+import jakarta.validation.Valid;
+import jakarta.validation.constraints.NotBlank;
+import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.Size;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.validation.annotation.Validated;
+
+import java.time.Duration;
+
+@Validated
+@ConfigurationProperties(prefix = "app.security")
+public record AuthProperties (
+        @NotBlank @Size(min = 32) String jwtSecret,
+        @Valid @NotNull Expiration expiration
+) {
+
+    /**
+     *
+     * @param jwt
+     * @param refreshToken
+     * @param tokenFamily
+     * @param gracePeriod
+     */
+    public record Expiration (
+            @NotNull Duration jwt,
+            @NotNull Duration refreshToken,
+            @NotNull Duration tokenFamily,
+            @NotNull Duration gracePeriod
+    ) {}
+}

src/main/java/com/ddf/vodsystem/entities/RefreshToken.java

@@ -0,0 +1,37 @@
+package com.ddf.vodsystem.entities;
+
+import jakarta.persistence.*;
+import lombok.Data;
+import org.hibernate.annotations.CreationTimestamp;
+
+import java.time.Instant;
+
+@Entity
+@Table(name = "refresh_tokens")
+@Data
+public class RefreshToken {
+    @Id
+    @Column(name = "id", nullable = false, unique = true)
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "family_id", nullable = false)
+    private TokenFamily tokenFamily;
+
+    @Column(name = "token_hash", unique = true, nullable = false, length = 32)
+    private byte[] tokenHash;
+
+    @Column(name = "created_at", nullable = false)
+    @CreationTimestamp
+    private Instant createdAt;
+
+    @Column(name = "expires_at", nullable = false)
+    private Instant expiresAt;
+
+    @Column(name = "used_at")
+    private Instant usedAt;
+
+    @Column(name = "revoked_at")
+    private Instant revokedAt;
+}

src/main/java/com/ddf/vodsystem/entities/TokenFamily.java

@@ -0,0 +1,31 @@
+package com.ddf.vodsystem.entities;
+
+import jakarta.persistence.*;
+import lombok.Data;
+import org.hibernate.annotations.CreationTimestamp;
+
+import java.time.Instant;
+
+@Entity
+@Table(name = "token_families")
+@Data
+public class TokenFamily {
+    @Id
+    @Column(name = "id", nullable = false, unique = true)
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "user_id", nullable = false)
+    private User user;
+
+    @Column(name = "created_at", nullable = false)
+    @CreationTimestamp
+    private Instant createdAt;
+
+    @Column(name = "expires_at", nullable = false)
+    private Instant expiresAt;
+
+    @Column(name = "revoked_at")
+    private Instant revokedAt;
+}

src/main/java/com/ddf/vodsystem/repositories/RefreshTokenRepository.java

@@ -0,0 +1,17 @@
+package com.ddf.vodsystem.repositories;
+
+import com.ddf.vodsystem.entities.RefreshToken;
+import jakarta.persistence.LockModeType;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Lock;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.stereotype.Repository;
+
+import java.util.Optional;
+
+@Repository
+public interface RefreshTokenRepository extends JpaRepository<RefreshToken, Long> {
+    @Lock(LockModeType.PESSIMISTIC_WRITE)
+    @Query("SELECT r FROM RefreshToken r WHERE r.tokenHash = ?1")
+    Optional<RefreshToken> findByHash(byte[] tokenHash);
+}

src/main/java/com/ddf/vodsystem/repositories/TokenFamilyRepository.java

@@ -0,0 +1,10 @@
+package com.ddf.vodsystem.repositories;
+
+import com.ddf.vodsystem.entities.TokenFamily;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface TokenFamilyRepository extends JpaRepository<TokenFamily, Long> {
+}

src/main/java/com/ddf/vodsystem/security/GoogleAuthConfig.java

@@ -0,0 +1,28 @@
+package com.ddf.vodsystem.security;
+
+import com.google.api.client.googleapis.auth.oauth2.GoogleIdTokenVerifier;
+import com.google.api.client.http.javanet.NetHttpTransport;
+import com.google.api.client.json.gson.GsonFactory;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import java.util.Collections;
+
+@Configuration
+public class GoogleAuthConfig {
+
+    /**
+     * Provides the verifier used to validate Google ID tokens issued for this application's client ID.
+     *
+     * @param googleClientId the OAuth client ID that tokens must be issued for
+     * @return the configured {@link GoogleIdTokenVerifier}
+     */
+    @Bean
+    public GoogleIdTokenVerifier googleIdTokenVerifier(
+            @Value("${spring.security.oauth2.client.registration.google.client-id}") String googleClientId) {
+        return new GoogleIdTokenVerifier.Builder(new NetHttpTransport(), new GsonFactory())
+                .setAudience(Collections.singletonList(googleClientId))
+                .build();
+    }
+}

src/main/java/com/ddf/vodsystem/security/GoogleVerifierService.java

@@ -0,0 +1,49 @@
+package com.ddf.vodsystem.security;
+
+import com.ddf.vodsystem.dto.GoogleUser;
+import com.ddf.vodsystem.exceptions.NotAuthenticated;
+import com.google.api.client.googleapis.auth.oauth2.GoogleIdToken;
+import com.google.api.client.googleapis.auth.oauth2.GoogleIdTokenVerifier;
+import org.springframework.stereotype.Service;
+
+import java.io.IOException;
+import java.security.GeneralSecurityException;
+
+@Service
+public class GoogleVerifierService {
+    private final GoogleIdTokenVerifier verifier;
+
+    public GoogleVerifierService(GoogleIdTokenVerifier verifier) {
+        this.verifier = verifier;
+    }
+
+    public GoogleUser verify(String idToken) {
+        GoogleIdToken token;
+        try {
+            token = verifier.verify(idToken);
+        } catch (GeneralSecurityException | IOException e) {
+            throw new NotAuthenticated("Invalid ID token: " + e.getMessage());
+        }
+
+        if (token == null) {
+            throw new NotAuthenticated("Invalid ID token");
+        }
+
+        String googleId = token.getPayload().getSubject();
+
+        if (googleId == null) {
+            throw new NotAuthenticated("Google ID does not exist");
+        }
+
+        if (!Boolean.TRUE.equals(token.getPayload().getEmailVerified())) {
+            throw new NotAuthenticated("Email not verified");
+        }
+
+        return new GoogleUser(
+                googleId,
+                token.getPayload().getEmail(),
+                (String) token.getPayload().get("name"),
+                (String) token.getPayload().get("picture")
+        );
+    }
+}

src/main/java/com/ddf/vodsystem/security/JwtService.java

@@ -7,6 +7,7 @@ import com.auth0.jwt.algorithms.Algorithm;
 import com.auth0.jwt.exceptions.JWTDecodeException;
 import com.auth0.jwt.exceptions.TokenExpiredException;
 import com.auth0.jwt.interfaces.DecodedJWT;
+import com.ddf.vodsystem.dto.properties.AuthProperties;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.security.oauth2.jwt.JwtException;
 import org.springframework.stereotype.Service;
@@ -20,10 +21,9 @@ public class JwtService {
     private static final String USER_ID_CLAIM = "userId";
     private static final String ISSUER = "vodsystem";
 
-    public JwtService(@Value("${jwt.secret.key}") String jwtSecretKey,
+    public JwtService(AuthProperties props) {
-                      @Value("${jwt.expiration}") long jwtExpiration) {
+        this.jwtExpiration = props.expiration().jwt().toMillis();
-        this.jwtExpiration = jwtExpiration;
+        this.algorithm = Algorithm.HMAC256(props.jwtSecret());
-        this.algorithm = Algorithm.HMAC256(jwtSecretKey);
     }
 
     /**

src/main/java/com/ddf/vodsystem/security/TokenService.java

@@ -0,0 +1,157 @@
+package com.ddf.vodsystem.security;
+
+import com.ddf.vodsystem.dto.properties.AuthProperties;
+import com.ddf.vodsystem.entities.RefreshToken;
+import com.ddf.vodsystem.entities.TokenFamily;
+import com.ddf.vodsystem.entities.User;
+import com.ddf.vodsystem.exceptions.NotAuthenticated;
+import com.ddf.vodsystem.repositories.RefreshTokenRepository;
+import com.ddf.vodsystem.repositories.TokenFamilyRepository;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+import java.time.Clock;
+import java.time.Duration;
+import java.time.Instant;
+import java.util.HexFormat;
+
+@Service
+public class TokenService {
+    private static final SecureRandom RNG = new SecureRandom();
+    private static final HexFormat HEX = HexFormat.of();
+
+    private final Clock clock;
+
+    private final TokenFamilyRepository tokenFamilyRepository;
+    private final RefreshTokenRepository refreshTokenRepository;
+
+    private final Duration tokenFamilyExpiration;
+    private final Duration refreshTokenExpiration;
+    private final Duration refreshGracePeriod;
+
+    public TokenService (
+            TokenFamilyRepository tokenFamilyRepository,
+            RefreshTokenRepository refreshTokenRepository,
+            AuthProperties props,
+            Clock clock
+    ) {
+        this.tokenFamilyRepository = tokenFamilyRepository;
+        this.refreshTokenRepository = refreshTokenRepository;
+        this.clock = clock;
+
+        this.refreshTokenExpiration = props.expiration().refreshToken();
+        this.tokenFamilyExpiration = props.expiration().tokenFamily();
+        this.refreshGracePeriod = props.expiration().gracePeriod();
+    }
+
+    @Transactional
+    public String createSession(User user) {
+        Instant now = Instant.now(clock);
+
+        TokenFamily tokenFamily = new TokenFamily();
+        tokenFamily.setUser(user);
+        tokenFamily.setCreatedAt(now);
+        tokenFamily.setExpiresAt(now.plusMillis(tokenFamilyExpiration.toMillis()));
+        tokenFamilyRepository.save(tokenFamily);
+
+        byte[] token = generateRandomBytes(32);
+
+        createRefreshToken(
+                token,
+                tokenFamily
+        );
+
+        return HEX.formatHex(token);
+    }
+
+    @Transactional(noRollbackFor = NotAuthenticated.class)
+    public Rotation rotate(String hexToken) {
+        if (hexToken == null || hexToken.isBlank()) {
+            throw new NotAuthenticated("Missing refresh token");
+        }
+
+        byte[] hash;
+        try {
+            hash = sha256(HEX.parseHex(hexToken));
+        } catch (IllegalArgumentException e) {
+            throw new NotAuthenticated("Malformed refresh token");
+        }
+
+        Instant now = Instant.now(clock);
+
+        // Check Token is real
+        RefreshToken refreshToken = refreshTokenRepository.findByHash(hash)
+                .orElseThrow(() -> new NotAuthenticated("No such refresh token"));
+
+        // Find Token Family
+        TokenFamily tokenFamily = refreshToken.getTokenFamily();
+
+        if (tokenFamily.getRevokedAt() != null) {
+            throw new NotAuthenticated("Token family has been revoked");
+        }
+
+        // Reuse Check
+        if (refreshToken.getUsedAt() != null && now.isAfter(refreshToken.getUsedAt().plus(refreshGracePeriod))) {
+            tokenFamily.setRevokedAt(now);
+            tokenFamilyRepository.save(tokenFamily);
+            throw new NotAuthenticated("Refresh token already being used");
+        }
+
+        // Expiry Check
+        if (
+                now.isAfter(refreshToken.getExpiresAt()) ||
+                now.isAfter(tokenFamily.getExpiresAt())
+        ) {
+            throw new NotAuthenticated("Refresh token or family expired");
+        }
+
+        // Invalidate old token, unless we're within the grace period, otherwise the grace gets extended
+        if (refreshToken.getUsedAt() == null) {
+            refreshToken.setUsedAt(now);
+            refreshTokenRepository.save(refreshToken);
+        }
+
+        byte[] newRawToken = generateRandomBytes(32);
+        createRefreshToken(
+                newRawToken,
+                tokenFamily
+        );
+
+        return new Rotation(tokenFamily.getUser().getId(), HEX.formatHex(newRawToken));
+    }
+
+    public record Rotation(Long userId, String newRefreshToken) {}
+
+    private static byte[] sha256(byte[] in) {
+        try {
+            return MessageDigest.getInstance("SHA-256").digest(in);
+        } catch (NoSuchAlgorithmException e) {
+            throw new IllegalStateException(e);
+        }
+    }
+
+    private byte[] generateRandomBytes(int length) {
+        byte[] bytes = new byte[length];
+        RNG.nextBytes(bytes);
+        return bytes;
+    }
+
+
+    private RefreshToken createRefreshToken(
+            byte[] token,
+            TokenFamily tokenFamily
+    ) {
+        Instant now = Instant.now(clock);
+
+        RefreshToken refreshToken = new RefreshToken();
+        refreshToken.setTokenFamily(tokenFamily);
+        refreshToken.setTokenHash(sha256(token));
+        refreshToken.setCreatedAt(now);
+        refreshToken.setExpiresAt(now.plusMillis(refreshTokenExpiration.toMillis()));
+        return refreshTokenRepository.save(refreshToken);
+    }
+
+}

src/main/java/com/ddf/vodsystem/services/UserService.java

@@ -1,47 +1,40 @@
 package com.ddf.vodsystem.services;
 
+import com.ddf.vodsystem.dto.GoogleUser;
+import com.ddf.vodsystem.dto.TokenPackage;
 import com.ddf.vodsystem.entities.User;
 import com.ddf.vodsystem.exceptions.NotAuthenticated;
 import com.ddf.vodsystem.repositories.UserRepository;
+import com.ddf.vodsystem.security.GoogleVerifierService;
 import com.ddf.vodsystem.security.JwtService;
-import com.google.api.client.googleapis.auth.oauth2.GoogleIdToken;
+import com.ddf.vodsystem.security.TokenService;
-import com.google.api.client.http.javanet.NetHttpTransport;
+import org.springframework.transaction.annotation.Transactional;
-import com.google.api.client.json.JsonFactory;
-import com.google.api.client.json.gson.GsonFactory;
-import org.springframework.beans.factory.annotation.Value;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.context.SecurityContextHolder;
-import com.google.api.client.googleapis.auth.oauth2.GoogleIdTokenVerifier;
 import org.springframework.stereotype.Service;
 
-import java.io.IOException;
-import java.security.GeneralSecurityException;
 import java.security.SecureRandom;
 import java.time.Instant;
-import java.util.Collections;
 import java.util.HexFormat;
 import java.util.Optional;
 
 @Service
 public class UserService {
-    private final GoogleIdTokenVerifier verifier;
+    private final GoogleVerifierService googleVerifierService;
     private final UserRepository userRepository;
     private final JwtService jwtService;
 
     private static final SecureRandom SECURE_RANDOM = new SecureRandom();
+    private final TokenService tokenService;
 
     public UserService(UserRepository userRepository,
                        JwtService jwtService,
-                       @Value("${google.client.id}") String googleClientId) {
+                       GoogleVerifierService googleVerifierService,
+                       TokenService tokenService) {
         this.userRepository = userRepository;
-
+        this.googleVerifierService = googleVerifierService;
-        NetHttpTransport transport = new NetHttpTransport();
-        JsonFactory jsonFactory = new GsonFactory();
-
-        this.verifier = new GoogleIdTokenVerifier.Builder(transport, jsonFactory)
-                .setAudience(Collections.singletonList(googleClientId))
-                .build();
         this.jwtService = jwtService;
+        this.tokenService = tokenService;
     }
 
     /**
@@ -74,18 +67,22 @@ public class UserService {
      * @return a signed JWT for the authenticated user
      * @throws NotAuthenticated if the token is invalid or its subject is missing
      */
-    public String login(String idToken) {
+    @Transactional
-        GoogleIdToken googleIdToken = getGoogleIdToken(idToken);
+    public TokenPackage login(String idToken) {
-        String googleId = googleIdToken.getPayload().getSubject();
+        GoogleUser googleUser = googleVerifierService.verify(idToken);
+        User user = createOrUpdateGoogleUser(googleUser);
 
-        if (googleId == null) {
+        String refreshToken = tokenService.createSession(user);
-            throw new NotAuthenticated("Invalid ID token");
+        String jwt = jwtService.generateToken(user.getId());
+
+        return new TokenPackage(refreshToken, jwt);
     }
 
-        User googleUser = getGoogleUser(googleIdToken);
+    public TokenPackage refresh(String refreshToken) {
-        User user = createOrUpdateUser(googleUser);
+        TokenService.Rotation rotation = tokenService.rotate(refreshToken);
+        String jwt = jwtService.generateToken(rotation.userId());
 
-        return jwtService.generateToken(user.getId());
+        return new TokenPackage(rotation.newRefreshToken(), jwt);
     }
 
     /**
@@ -98,51 +95,30 @@ public class UserService {
         return userRepository.findByStreamKey(streamKey);
     }
 
-    private User createOrUpdateUser(User user) {
+    private User createOrUpdateGoogleUser(GoogleUser googleUser) {
-        Optional<User> existingUser = userRepository.findByGoogleId(user.getGoogleId());
+        Optional<User> existingUser = userRepository.findByGoogleId(googleUser.googleId());
+        User user;
 
         if (existingUser.isEmpty()) {
+            user = new User();
+            user.setGoogleId(googleUser.googleId());
+            user.setUsername(googleUser.email());
             user.setRole(0);
             user.setCreatedAt(Instant.now());
-            user.setStreamKey(generateStreamKey());
+            user.setStreamKey(HexFormat.of().formatHex(generateRandomBytes(24)));
-            return userRepository.saveAndFlush(user);
+        } else {
+            user = existingUser.get();
         }
 
-        User existing = existingUser.get();
+        user.setEmail(googleUser.email());
-        existing.setEmail(user.getEmail());
+        user.setName(googleUser.name());
-        existing.setName(user.getName());
+        user.setProfilePictureUrl(googleUser.profilePictureUrl());
-        existing.setProfilePictureUrl(user.getProfilePictureUrl());
+        return userRepository.save(user);
-        existing.setUsername(user.getUsername());
-        return userRepository.saveAndFlush(existing);
     }
 
-    private User getGoogleUser(GoogleIdToken idToken) {
+    private byte[] generateRandomBytes(int length) {
-        String googleId = idToken.getPayload().getSubject();
+        byte[] bytes = new byte[length];
-        String email = idToken.getPayload().getEmail();
-        String name = (String) idToken.getPayload().get("name");
-        String profilePictureUrl = (String) idToken.getPayload().get("picture");
-
-        User user = new User();
-        user.setGoogleId(googleId);
-        user.setEmail(email);
-        user.setName(name);
-        user.setUsername(email);
-        user.setProfilePictureUrl(profilePictureUrl);
-
-        return user;
-    }
-
-    private GoogleIdToken getGoogleIdToken(String idToken) {
-        try {
-            return verifier.verify(idToken);
-        } catch (GeneralSecurityException | IOException e) {
-            throw new NotAuthenticated("Invalid ID token: " + e.getMessage());
-        }
-    }
-
-    private String generateStreamKey() {
-        byte[] bytes = new byte[24];
         SECURE_RANDOM.nextBytes(bytes);
-        return HexFormat.of().formatHex(bytes);
+        return bytes;
     }
 }

src/main/resources/application.properties

@@ -20,8 +20,16 @@ spring.flyway.locations=classpath:db/migrations
 spring.security.oauth2.client.registration.google.client-id=${GOOGLE_CLIENT_ID}
 spring.security.oauth2.client.registration.google.client-secret=${GOOGLE_CLIENT_SECRET}
 spring.security.oauth2.client.registration.google.scope=profile,email
-jwt.secret.key=${JWT_SECRET_KEY}
+app.security.jwt-secret=${JWT_SECRET_KEY}
-jwt.expiration=3600000
+# 1 Hour
+app.security.expiration.jwt=3600000
+# 7 days
+app.security.expiration.refresh-token=604800000
+# 90 days
+app.security.expiration.token-family=7776000000
+
+# 5 seconds
+app.security.expiration.grace-period=5000
 
 # Frontend
 frontend.url=${FRONTEND_URL}

src/main/resources/db/migrations/V2__refresh_tokens.sql

@@ -0,0 +1,27 @@
+CREATE TABLE IF NOT EXISTS token_families
+(
+    id BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL REFERENCES users (id) ON DELETE CASCADE,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    expires_at TIMESTAMPTZ NOT NULL,
+    revoked_at TIMESTAMPTZ
+);
+
+CREATE INDEX IF NOT EXISTS idx_token_families_user_id
+    ON token_families (user_id);
+
+CREATE TABLE IF NOT EXISTS refresh_tokens
+(
+    id BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
+    family_id BIGINT NOT NULL REFERENCES token_families (id) ON DELETE CASCADE,
+    token_hash BYTEA NOT NULL UNIQUE, -- unique automatically creates a B-tree index
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    expires_at TIMESTAMPTZ NOT NULL,
+    used_at TIMESTAMPTZ,
+    revoked_at TIMESTAMPTZ,
+
+    CONSTRAINT refresh_tokens_hash_len CHECK (octet_length(token_hash) = 32)
+);
+
+CREATE INDEX IF NOT EXISTS idx_refresh_tokens_family_id
+    ON refresh_tokens (family_id);

src/test/java/com/ddf/vodsystem/security/TokenServiceTest.java

@@ -0,0 +1,327 @@
+package com.ddf.vodsystem.security;
+
+import com.ddf.vodsystem.dto.properties.AuthProperties;
+import com.ddf.vodsystem.entities.RefreshToken;
+import com.ddf.vodsystem.entities.TokenFamily;
+import com.ddf.vodsystem.entities.User;
+import com.ddf.vodsystem.exceptions.NotAuthenticated;
+import com.ddf.vodsystem.repositories.RefreshTokenRepository;
+import com.ddf.vodsystem.repositories.TokenFamilyRepository;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Captor;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import java.time.*;
+import java.util.HexFormat;
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.*;
+
+class MutableClock extends Clock {
+    private Instant now;
+
+    MutableClock(Instant start) {
+        this.now = start;
+    }
+
+    void advance(Duration d) {
+        now = now.plus(d);
+    }
+
+    @Override public Instant instant() { return now; }
+    @Override public ZoneId getZone() { return ZoneOffset.UTC; }
+    @Override public Clock withZone(ZoneId zone) { return this; }
+}
+
+
+@ExtendWith(MockitoExtension.class)
+class TokenServiceTest {
+    @Mock private TokenFamilyRepository tokenFamilyRepository;
+    @Mock private RefreshTokenRepository refreshTokenRepository;
+
+    @Captor ArgumentCaptor<TokenFamily> familyCaptor;
+    @Captor ArgumentCaptor<RefreshToken> tokenCaptor;
+
+    private static final HexFormat HEX = HexFormat.of();
+    private static final String rawToken = "deadbeefdeadbeefdeadbeefdeadbeef";
+
+    AuthProperties authProperties;
+    TokenService tokenService;
+    MutableClock clock;
+
+    User createUser(Long id, String username, String email) {
+        User user = new User();
+        user.setId(id);
+        user.setUsername(username);
+        user.setEmail(email);
+        return user;
+    }
+
+    @BeforeEach
+    void setUp() {
+
+        authProperties = new AuthProperties(
+                "a-secret",
+                new AuthProperties.Expiration(
+                        Duration.ofSeconds(10),
+                        Duration.ofSeconds(10),
+                        Duration.ofSeconds(10),
+                        Duration.ofSeconds(10)
+                )
+        );
+
+        clock = new MutableClock(Instant.parse("2026-01-01T00:00:00Z"));
+
+        tokenService = new TokenService(
+                tokenFamilyRepository,
+                refreshTokenRepository,
+                authProperties,
+                clock
+        );
+    }
+
+    @Nested
+    @DisplayName("createSession()")
+    class createSession {
+        @Test
+        void createSession_createsTokenFamily() {
+            User user = createUser(1L, "user", "user@gmail.com");
+
+            tokenService.createSession(user);
+
+            verify(tokenFamilyRepository).save(familyCaptor.capture());
+            verify(refreshTokenRepository).save(tokenCaptor.capture());
+
+            TokenFamily tokenFamily = familyCaptor.getValue();
+            RefreshToken refreshToken = tokenCaptor.getValue();
+
+            assertSame(tokenFamily.getUser(), user);
+            assertSame(refreshToken.getTokenFamily(), tokenFamily);
+            assertEquals(
+                    tokenFamily.getExpiresAt(),
+                    clock.instant().plusMillis(authProperties.expiration().tokenFamily().toMillis())
+            );
+        }
+
+        @Test
+        void createSession_savesRefreshTokenCreatedAtAndExpires() {
+            User user = createUser(1L, "user", "user");
+
+            tokenService.createSession(user);
+
+            verify(refreshTokenRepository).save(tokenCaptor.capture());
+            RefreshToken refreshToken = tokenCaptor.getValue();
+
+            assertEquals(refreshToken.getCreatedAt(), clock.instant());
+            assertEquals(
+                    refreshToken.getExpiresAt(),
+                    clock.instant().plusMillis(authProperties.expiration().refreshToken().toMillis())
+            );
+        }
+
+        @Test
+        void createSession_returnsHexTokenOf64Characters() {
+            User user = createUser(1L, "user", "user");
+
+            String token = tokenService.createSession(user);
+
+            assertEquals(64, token.length());
+            assertTrue(token.matches("[0-9a-fA-F]+"), () -> "not hex: " + token);
+        }
+
+        @Test
+        void createSession_doesNotStoreRawToken() {
+            User user = createUser(1L, "user", "user");
+
+            String token = tokenService.createSession(user);
+
+            verify(refreshTokenRepository).save(tokenCaptor.capture());
+            RefreshToken refreshToken = tokenCaptor.getValue();
+
+            assertNotEquals(refreshToken.getTokenHash(), HEX.parseHex(token));
+        }
+    }
+
+    // Rotate
+    @Nested
+    @DisplayName("rotate()")
+    class rotate {
+        // Input val
+        @Test
+        void nullToken_throwsNotAuthenticated() {
+            assertThrows(
+                    NotAuthenticated.class,
+                    () -> tokenService.rotate(null)
+            );
+        }
+
+        @Test
+        void blankToken_throwsNotAuthenticated() {
+            assertThrows(
+                    NotAuthenticated.class,
+                    () -> tokenService.rotate("")
+            );
+        }
+
+        // Invalid cases
+        @Test
+        void unknownToken_throwsNotAuthenticated() {
+            when(refreshTokenRepository.findByHash(any())).thenReturn(
+                    Optional.empty()
+            );
+
+            assertThrows(
+                    NotAuthenticated.class,
+                    () -> tokenService.rotate(rawToken)
+            );
+        }
+
+        @Test
+        void revokedFamily_throwsNotAuthenticated() {
+            TokenFamily tokenFamily = new TokenFamily();
+            tokenFamily.setId(1L);
+            tokenFamily.setRevokedAt(Instant.now(clock));
+
+            RefreshToken refreshToken = new RefreshToken();
+            refreshToken.setTokenFamily(tokenFamily);
+
+            clock.advance(Duration.ofMinutes(1));
+
+            when(refreshTokenRepository.findByHash(any())).thenReturn(
+                    Optional.of(refreshToken)
+            );
+
+            assertThrows(
+                    NotAuthenticated.class,
+                    () -> tokenService.rotate(rawToken)
+            );
+        }
+
+        // Happy Path
+        @Test
+        void unusedToken_returnsUserIdAndRefreshToken() {
+            TokenFamily tokenFamily = new TokenFamily();
+            tokenFamily.setId(1L);
+            tokenFamily.setUser(createUser(1L, "user", "user"));
+            tokenFamily.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            RefreshToken refreshToken = new RefreshToken();
+            refreshToken.setTokenFamily(tokenFamily);
+            refreshToken.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            when(refreshTokenRepository.findByHash(any()))
+                    .thenReturn(Optional.of(refreshToken));
+
+            TokenService.Rotation rotation = tokenService.rotate(rawToken);
+
+            assertEquals(1L, rotation.userId());
+            assertNotEquals(rawToken, rotation.newRefreshToken());
+        }
+
+        @Test
+        void unsedToken_savesRefreshToken() {
+            TokenFamily tokenFamily = new TokenFamily();
+            tokenFamily.setId(1L);
+            tokenFamily.setUser(createUser(1L, "user", "user"));
+            tokenFamily.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            RefreshToken refreshToken = new RefreshToken();
+            refreshToken.setTokenFamily(tokenFamily);
+            refreshToken.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            when(refreshTokenRepository.findByHash(any()))
+                    .thenReturn(Optional.of(refreshToken));
+
+            tokenService.rotate(rawToken);
+
+            verify(refreshTokenRepository, times(2)).save(tokenCaptor.capture());
+
+            RefreshToken newToken = tokenCaptor.getAllValues().stream()
+                    .filter(t -> t.getUsedAt() == null)
+                    .reduce((a, b) -> { throw new AssertionError("expected exactly one unused token saved"); })
+                    .orElseThrow(() -> new AssertionError("no unused token was saved"));
+
+            assertNotEquals(refreshToken.getTokenHash(), newToken.getTokenHash());
+            assertEquals(refreshToken.getTokenFamily().getUser(), newToken.getTokenFamily().getUser());        // same owner
+            assertEquals(refreshToken.getTokenFamily(), newToken.getTokenFamily()); // same rotation family, if you model one
+            assertNull(newToken.getUsedAt());
+        }
+
+        @Test
+        void ununsedToken_savesOldTokenWithUsedAt() {
+            TokenFamily tokenFamily = new TokenFamily();
+            tokenFamily.setId(1L);
+            tokenFamily.setUser(createUser(1L, "user", "user"));
+            tokenFamily.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            RefreshToken refreshToken = new RefreshToken();
+            refreshToken.setTokenFamily(tokenFamily);
+            refreshToken.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            when(refreshTokenRepository.findByHash(any()))
+                    .thenReturn(Optional.of(refreshToken));
+
+            tokenService.rotate(rawToken);
+
+            verify(refreshTokenRepository, times(2)).save(tokenCaptor.capture());
+
+            RefreshToken savedToken = tokenCaptor.getAllValues().stream()
+                    .filter(t -> t.getUsedAt() != null)
+                    .reduce((a, b) -> { throw new AssertionError("expected exactly one unused token saved"); })
+                    .orElseThrow(() -> new AssertionError("used_at field not set in any token"));
+
+            assertEquals(savedToken.getUsedAt(), clock.instant());
+        }
+
+        @Test
+        void unusedToken_doesNotRevokeFamily() {
+            TokenFamily tokenFamily = new TokenFamily();
+            tokenFamily.setId(1L);
+            tokenFamily.setUser(createUser(1L, "user", "user"));
+            tokenFamily.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            RefreshToken refreshToken = new RefreshToken();
+            refreshToken.setTokenFamily(tokenFamily);
+            refreshToken.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            when(refreshTokenRepository.findByHash(any()))
+                    .thenReturn(Optional.of(refreshToken));
+
+            tokenService.rotate(rawToken);
+
+            verify(refreshTokenRepository, times(2)).save(tokenCaptor.capture());
+            RefreshToken newToken = tokenCaptor.getAllValues().stream()
+                    .filter(t -> t.getUsedAt() == null)
+                    .reduce((a, b) -> { throw new AssertionError("expected exactly one unused token saved"); })
+                    .orElseThrow(() -> new AssertionError("no unused token was saved"));
+            assertNull(newToken.getTokenFamily().getRevokedAt());
+        }
+
+        @Test
+        void unusedToken_newTokenIsDifferentFromOldToken() {
+            TokenFamily tokenFamily = new TokenFamily();
+            tokenFamily.setId(1L);
+            tokenFamily.setUser(createUser(1L, "user", "user"));
+            tokenFamily.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            RefreshToken refreshToken = new RefreshToken();
+            refreshToken.setTokenHash(rawToken.getBytes());
+            refreshToken.setTokenFamily(tokenFamily);
+            refreshToken.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            when(refreshTokenRepository.findByHash(any()))
+                    .thenReturn(Optional.of(refreshToken));
+
+            TokenService.Rotation rotation = tokenService.rotate(rawToken);
+            assertNotEquals(rawToken, rotation.newRefreshToken());
+        }
+    }
+}

src/test/java/com/ddf/vodsystem/services/UserServiceTest.java

@@ -0,0 +1,7 @@
+package com.ddf.vodsystem.services;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class UserServiceTest {
+
+}