revised TokenController.provideToken

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

de.srsoftware.oidc.api/src/main/java/de/srsoftware/oidc/api/AuthResult.java

@@ -0,0 +1,7 @@
+/* © SRSoftware 2024 */
+package de.srsoftware.oidc.api;
+
+import java.util.Set;
+
+public record AuthResult(AuthorizedScopes authorizedScopes, Set<String> unauthorizedScopes, String authCode) {
+}

de.srsoftware.oidc.api/src/main/java/de/srsoftware/oidc/api/Authorization.java

@@ -0,0 +1,5 @@
+/* © SRSoftware 2024 */
+package de.srsoftware.oidc.api;
+
+public record Authorization(String clientId, String userId, AuthorizedScopes scopes) {
+}

de.srsoftware.oidc.api/src/main/java/de/srsoftware/oidc/api/AuthorizedScope.java

@@ -1,7 +0,0 @@
-/* © SRSoftware 2024 */
-package de.srsoftware.oidc.api;
-
-import java.time.Instant;
-
-public record AuthorizedScope(String scope, Instant expiration) {
-}

de.srsoftware.oidc.api/src/main/java/de/srsoftware/oidc/api/AuthorizedScopes.java

@@ -0,0 +1,8 @@
+/* © SRSoftware 2024 */
+package de.srsoftware.oidc.api;
+
+import java.time.Instant;
+import java.util.Set;
+
+public record AuthorizedScopes(Set<String> scopes, Instant expiration) {
+}

de.srsoftware.oidc.api/src/main/java/de/srsoftware/oidc/api/ClaimAuthorizationService.java

@@ -3,12 +3,10 @@ package de.srsoftware.oidc.api;
 
 import java.time.Instant;
 import java.util.Collection;
-import java.util.List;
-import java.util.Set;
+import java.util.Optional;
 
 public interface ClaimAuthorizationService {
-	public record AuthResult(List<AuthorizedScope> authorizedScopes, Set<String> unauthorizedScopes, String authCode) {
-	}
-	AuthResult	          getAuthorization(User user, Client client, Collection<String> scopes);
 	ClaimAuthorizationService authorize(User user, Client client, Collection<String> scopes, Instant expiration);
+	Optional<Authorization>   consumeAuthorization(String authCode);
+	AuthResult	          getAuthorization(User user, Client client, Collection<String> scopes);
 }

de.srsoftware.oidc.api/src/main/java/de/srsoftware/oidc/api/Constants.java

@@ -1,6 +1,7 @@
 /* © SRSoftware 2024 */
 package de.srsoftware.oidc.api;
 
+
 public class Constants {
 	public static final String ACCESS_TOKEN	  = "access_token";
 	public static final String APP_NAME	  = "LightOIDC";
@@ -21,6 +22,8 @@ public class Constants {
 	public static final String EXPIRES_IN	  = "expires_in";
 	public static final String GRANT_TYPE	  = "grant_type";
 	public static final String ID_TOKEN	  = "id_token";
+	public static final String INVALID_CLIENT	  = "invalid_client";
+	public static final String INVALID_GRANT	  = "invalid_grant";
 	public static final String INVALID_REDIRECT_URI	  = "invalid_request_uri";
 	public static final String INVALID_REQUEST	  = "invalid_request";
 	public static final String INVALID_REQUEST_OBJECT = "invalid_request_object";
@@ -37,4 +40,5 @@ public class Constants {
 	public static final String STATE	  = "state";
 	public static final String TOKEN	  = "token";
 	public static final String TOKEN_TYPE	  = "token_type";
+	public static final String UNAUTHORIZED_CLIENT	  = "unauthorized_client";
 }

de.srsoftware.oidc.api/src/main/java/de/srsoftware/oidc/api/PathHandler.java

@@ -11,10 +11,7 @@ import com.sun.net.httpserver.HttpExchange;
 import com.sun.net.httpserver.HttpHandler;
 import com.sun.net.httpserver.HttpServer;
 import java.io.IOException;
-import java.util.Arrays;
-import java.util.List;
-import java.util.Map;
-import java.util.Optional;
+import java.util.*;
 import java.util.stream.Stream;
 import org.json.JSONObject;
 
@@ -30,6 +27,9 @@ public abstract class PathHandler implements HttpHandler {
 
 	private String[] paths;
 
+	public record BasicAuth(String userId, String pass) {
+	}
+
 	public class Bond {
 		Bond(String[] paths) {
 			PathHandler.this.paths = paths;
@@ -102,6 +102,16 @@ public abstract class PathHandler implements HttpHandler {
 			return getHeader(ex, AUTHORIZATION);
 		}
 
+		public static Optional<BasicAuth> getBasicAuth(HttpExchange ex) {
+			return getAuthToken(ex)
+			    .filter(token -> token.startsWith("Basic "))  //
+			    .map(token -> token.substring(6))
+			    .map(Base64.getDecoder()::decode)
+			    .map(bytes -> new String(bytes, UTF_8))
+			    .map(token -> token.split(":", 2))
+			    .map(arr -> new BasicAuth(arr[0], arr[1]));
+		}
+
 		public static Optional<String> getBearer(HttpExchange ex) {
 			return getAuthToken(ex).filter(token -> token.startsWith("Bearer ")).map(token -> token.substring(7));
 		}

de.srsoftware.oidc.backend/src/main/java/de/srsoftware/oidc/backend/ClientController.java

@@ -3,15 +3,16 @@ package de.srsoftware.oidc.backend;
 
 import static de.srsoftware.oidc.api.Constants.*;
 import static de.srsoftware.oidc.api.Permission.MANAGE_CLIENTS;
+import static de.srsoftware.utils.Optionals.emptyIfBlank;
 import static java.net.HttpURLConnection.*;
 
 import com.sun.net.httpserver.HttpExchange;
 import de.srsoftware.oidc.api.*;
+import de.srsoftware.utils.Optionals;
 import java.io.IOException;
 import java.time.Instant;
 import java.time.temporal.ChronoUnit;
 import java.util.*;
-import java.util.stream.Collectors;
 import org.json.JSONObject;
 
 public class ClientController extends Controller {
@@ -28,8 +29,8 @@ public class ClientController extends Controller {
 	private boolean authorizationError(HttpExchange ex, String errorCode, String description, String state) throws IOException {
 		var map = new HashMap<String, String>();
 		map.put(ERROR, errorCode);
-		if (description != null) map.put(ERROR_DESCRIPTION,description);
-		if (state != null) map.put(STATE,state);
+		emptyIfBlank(description).ifPresent(d -> map.put(ERROR_DESCRIPTION, d));
+		emptyIfBlank(state).ifPresent(s -> map.put(STATE, s));
 		return badRequest(ex, map);
 	}
 
@@ -66,7 +67,7 @@ public class ClientController extends Controller {
 		if (!client.redirectUris().contains(redirect)) authorizationError(ex, INVALID_REDIRECT_URI, "unknown redirect uri: %s".formatted(redirect), state);
 
 		client.nonce(json.has(NONCE) ? json.getString(NONCE) : null);
-		if (json.has(AUTHORZED)) {
+		if (json.has(AUTHORZED)) {  // user did consent
 			var authorized = json.getJSONObject(AUTHORZED);
 			var days       = authorized.getInt("days");
 			var list       = new ArrayList<String>();
@@ -78,9 +79,9 @@ public class ClientController extends Controller {
 		if (!authResult.unauthorizedScopes().isEmpty()) {
 			return sendContent(ex, Map.of("unauthorized_scopes", authResult.unauthorizedScopes(), "rp", client.name()));
 		}
-		var authorizedScopes = authResult.authorizedScopes().stream().map(AuthorizedScope::scope).collect(Collectors.joining(" "));
+		var joinedAuthorizedScopes = Optionals.nullable(authResult.authorizedScopes()).map(AuthorizedScopes::scopes).map(list -> String.join(" ", list));
 		var result	           = new HashMap<String, String>();
-		result.put(SCOPE, authorizedScopes);
+		joinedAuthorizedScopes.ifPresent(authorizedScopes -> result.put(SCOPE, authorizedScopes));
 		result.put(CODE, authResult.authCode());
 		if (state != null) result.put(STATE, state);
 		return sendContent(ex, result);

de.srsoftware.oidc.backend/src/main/java/de/srsoftware/oidc/backend/TokenController.java

@@ -2,18 +2,23 @@
 package de.srsoftware.oidc.backend;
 
 import static de.srsoftware.oidc.api.Constants.*;
+import static de.srsoftware.oidc.api.Constants.ERROR;
+import static de.srsoftware.utils.Optionals.emptyIfBlank;
 import static java.lang.System.Logger.Level.*;
-import static java.net.HttpURLConnection.HTTP_NOT_IMPLEMENTED;
+import static java.net.HttpURLConnection.HTTP_UNAUTHORIZED;
 
 import com.sun.net.httpserver.HttpExchange;
 import de.srsoftware.oidc.api.*;
 import java.io.IOException;
+import java.net.URLDecoder;
+import java.nio.charset.StandardCharsets;
 import java.util.*;
 import java.util.stream.Collectors;
 import org.jose4j.jwk.PublicJsonWebKey;
 import org.jose4j.jws.JsonWebSignature;
 import org.jose4j.jwt.JwtClaims;
 import org.jose4j.lang.JoseException;
+import org.json.JSONObject;
 
 public class TokenController extends PathHandler {
 	public record Configuration(String issuer, int tokenExpirationMinutes) {
@@ -46,36 +51,54 @@ public class TokenController extends PathHandler {
 		return notFound(ex);
 	}
 
+	private HashMap<String, String> tokenResponse(String errorCode, String description) throws IOException {
+		var map = new HashMap<String, String>();
+		map.put(ERROR, errorCode);
+		emptyIfBlank(description).ifPresent(d -> map.put(ERROR_DESCRIPTION, d));
+		return map;
+	}
+
 	private boolean provideToken(HttpExchange ex) throws IOException {
 		var map = deserialize(body(ex));
-		// TODO: check 	data, → https://openid.net/specs/openid-connect-core-1_0.html#TokenEndpoint
-		return sendEmptyResponse(HTTP_NOT_IMPLEMENTED, ex);
-		/*
+
 		var grantType = map.get(GRANT_TYPE);
-		if (!AUTH_CODE.equals(grantType)) return sendContent(ex, HTTP_BAD_REQUEST, Map.of(ERROR, "unknown grant type", GRANT_TYPE, grantType));
+		// verify grant type
+		if (!AUTH_CODE.equals(grantType)) return badRequest(ex, tokenResponse(INVALID_GRANT, "unknown grant type \"%s\"".formatted(grantType)));
 
-		var code	     = map.get(CODE);
-		var optAuthorization = authorizations.forCode(code);
-		if (optAuthorization.isEmpty()) return sendContent(ex, HTTP_BAD_REQUEST, Map.of(ERROR, "invalid auth code", CODE, code));
-		var authorization = optAuthorization.get();
+		var basicAuth = getBasicAuth(ex).orElse(null);
 
-		var clientId = map.get(CLIENT_ID);
-		if (!authorization.clientId().equals(clientId)) return sendContent(ex, HTTP_BAD_REQUEST, Map.of(ERROR, "invalid client id", CLIENT_ID, clientId));
+		var clientId  = basicAuth != null ? basicAuth.userId() : map.get(CLIENT_ID);
 		var optClient = clients.getClient(clientId);
-		if (optClient.isEmpty()) return sendContent(ex, HTTP_BAD_REQUEST, Map.of(ERROR, "unknown client", CLIENT_ID, clientId));
+		if (optClient.isEmpty()) return badRequest(ex, tokenResponse(INVALID_CLIENT, "unknown client \"%s\"".formatted(clientId)));
+
 		var client = optClient.get();
+		if (client.secret() != null) {	// for confidential clients:
+			// authenticate client by matching secret
+			String clientSecret = basicAuth != null ? basicAuth.pass() : map.get(CLIENT_SECRET);
+			if (clientSecret == null) return sendContent(ex, HTTP_UNAUTHORIZED, tokenResponse(INVALID_CLIENT, "client not authenticated"));
+			if (!client.secret().equals(clientSecret)) return sendContent(ex, HTTP_UNAUTHORIZED, tokenResponse(INVALID_CLIENT, "client not authenticated"));
+		}
 
-		var user = users.load(authorization.userId());
-		if (user.isEmpty()) return sendContent(ex, 500, Map.of(ERROR, "User not found"));
+		var authCode = map.get(CODE);
 
+		// verify that code is not re-used
+		var optAuthorization = authorizations.consumeAuthorization(authCode);
+		if (optAuthorization.isEmpty()) return badRequest(ex, tokenResponse(INVALID_GRANT, "invalid auth code: \"%s\"".formatted(authCode)));
+		var authorization = optAuthorization.get();
+
+		// verify authorization code was issued to the authenticated client
+		if (!authorization.clientId().equals(clientId)) return badRequest(ex, tokenResponse(UNAUTHORIZED_CLIENT, null));
+
+		// verify redirect URI
 		var uri = URLDecoder.decode(map.get(REDIRECT_URI), StandardCharsets.UTF_8);
-		if (!client.redirectUris().contains(uri)) sendContent(ex, HTTP_BAD_REQUEST, Map.of(ERROR, "unknown redirect uri", REDIRECT_URI, uri));
+		if (!client.redirectUris().contains(uri)) return badRequest(ex, tokenResponse(INVALID_REQUEST, "unknown redirect uri: \"%s\"".formatted(uri)));
+
+		// verify user is valid
+		var user = users.load(authorization.userId());
+		if (user.isEmpty()) return badRequest(ex, tokenResponse(INVALID_REQUEST, "unknown user"));
+
+		if (!authorization.scopes().scopes().contains(OPENID)) return badRequest(ex, tokenResponse(INVALID_REQUEST, "Token invalid for OpenID scope"));
 
-		if (client.secret() != null) {
-			String clientSecret = nullable(ex.getRequestHeaders().get(AUTHORIZATION)).map(list -> list.get(0)).filter(s -> s.startsWith("Basic ")).map(s -> s.substring(6)).map(s -> Base64.getDecoder().decode(s)).map(bytes -> new String(bytes, StandardCharsets.UTF_8)).filter(s -> s.startsWith("%s:".formatted(client.id()))).map(s -> s.substring(client.id().length() + 1).trim()).orElseGet(() -> map.get(CLIENT_SECRET));
-			if (clientSecret == null) return sendContent(ex, HTTP_BAD_REQUEST, Map.of(ERROR, "client secret missing"));
-			if (!client.secret().equals(clientSecret)) return sendContent(ex, HTTP_BAD_REQUEST, Map.of(ERROR, "client secret mismatch"));
-		}
 		String jwToken = createJWT(client, user.get());
 		ex.getResponseHeaders().add("Cache-Control", "no-store");
 		JSONObject response = new JSONObject();
@@ -83,8 +106,8 @@ public class TokenController extends PathHandler {
 		response.put(TOKEN_TYPE, BEARER);
 		response.put(EXPIRES_IN, 3600);
 		response.put(ID_TOKEN, jwToken);
-		LOG.log(DEBUG, jwToken);
-		return sendContent(ex, response);*/
+
+		return sendContent(ex, response);
 	}
 
 	private String createJWT(Client client, User user) {

de.srsoftware.oidc.datastore.file/src/main/java/de/srsoftware/oidc/datastore/file/FileStore.java

@@ -37,7 +37,7 @@ public class FileStore implements ClaimAuthorizationService, ClientService, Sess
 	private Duration	     sessionDuration = Duration.of(10, ChronoUnit.MINUTES);
 	private Map<String, Client>	     clients	     = new HashMap<>();
 	private Map<String, User>	     accessTokens    = new HashMap<>();
-	private Map<String, String>	     authCodes	     = new HashMap<>();
+	private Map<String, Authorization>   authCodes	     = new HashMap<>();
 
 	public FileStore(File storage, PasswordHasher<String> passwordHasher) throws IOException {
 		this.storageFile    = storage.toPath();
@@ -266,6 +266,11 @@ public class FileStore implements ClaimAuthorizationService, ClientService, Sess
 	}
 
 	/*** ClaimAuthorizationService methods ***/
+	private String authCode(User user, Client client, Authorization authorization) {
+		var code = uuid();
+		authCodes.put(code, authorization);
+		return code;
+	}
 
 	@Override
 	public ClaimAuthorizationService authorize(User user, Client client, Collection<String> scopes, Instant expiration) {
@@ -280,8 +285,10 @@ public class FileStore implements ClaimAuthorizationService, ClientService, Sess
 		return this;
 	}
 
-	private AuthResult unauthorized(Collection<String> scopes) {
-		return new AuthResult(List.of(), new HashSet<>(scopes), null);
+
+	@Override
+	public Optional<Authorization> consumeAuthorization(String authCode) {
+		return nullable(authCodes.remove(authCode));
 	}
 
 	@Override
@@ -292,24 +299,26 @@ public class FileStore implements ClaimAuthorizationService, ClientService, Sess
 		var clientScopes = userAuthorizations.has(client.id()) ? userAuthorizations.getJSONObject(client.id()) : null;
 		if (clientScopes == null) return unauthorized(scopes);
 		var     now	           = Instant.now();
-		var authorizedScopes   = new ArrayList<AuthorizedScope>();
+		var     authorizedScopes   = new HashSet<String>();
 		var     unauthorizedScopes = new HashSet<String>();
+		Instant earliestExpiration = null;
 		for (var scope : scopes) {
 			if (clientScopes.has(scope)) {
 				var expiration = Instant.ofEpochSecond(clientScopes.getLong(scope));
 				if (expiration.isAfter(now)) {
-					authorizedScopes.add(new AuthorizedScope(scope, expiration));
+					authorizedScopes.add(scope);
+					if (earliestExpiration == null || expiration.isBefore(earliestExpiration)) earliestExpiration = expiration;
 				} else {
 					unauthorizedScopes.add(scope);
 				}
 			}
 		}
-		return new AuthResult(authorizedScopes, unauthorizedScopes, authCode(user, client));
+
+		var authorization = new Authorization(client.id(), user.uuid(), new AuthorizedScopes(authorizedScopes, earliestExpiration));
+		return new AuthResult(authorization.scopes(), unauthorizedScopes, authCode(user, client, authorization));
 	}
 
-	private String authCode(User user, Client client) {
-		var code = uuid();
-		authCodes.put(user.uuid() + "@" + client.id(), code);
-		return code;
+	private AuthResult unauthorized(Collection<String> scopes) {
+		return new AuthResult(null, new HashSet<>(scopes), null);
 	}
 }