switch to basic auth for API access

src/main/java/de/rwth/idsg/steve/config/ApiAuthenticationManager.java

@@ -0,0 +1,140 @@
+/*
+ * SteVe - SteckdosenVerwaltung - https://github.com/steve-community/steve
+ * Copyright (C) 2013-2024 SteVe Community Team
+ * All Rights Reserved.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package de.rwth.idsg.steve.config;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.google.common.base.Strings;
+import com.google.common.cache.Cache;
+import com.google.common.cache.CacheBuilder;
+import de.rwth.idsg.steve.service.WebUserService;
+import de.rwth.idsg.steve.web.api.ApiControllerAdvice;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.BadCredentialsException;
+import org.springframework.security.authentication.DisabledException;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.AuthenticationException;
+import org.springframework.security.core.userdetails.User;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.security.web.AuthenticationEntryPoint;
+import org.springframework.stereotype.Component;
+
+import jakarta.servlet.ServletException;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * @author Sevket Goekay <[email protected]>
+ * @since 17.08.2024
+ */
+@Slf4j
+@Component
+@RequiredArgsConstructor
+public class ApiAuthenticationManager implements AuthenticationManager, AuthenticationEntryPoint {
+
+    // Because Guava's cache does not accept a null value
+    private static final UserDetails DUMMY_USER = new User("#", "#", Collections.emptyList());
+
+    private final WebUserService webUserService;
+    private final PasswordEncoder passwordEncoder;
+    private final ObjectMapper jacksonObjectMapper;
+
+    private final Cache<String, UserDetails> userCache = CacheBuilder.newBuilder()
+        .expireAfterWrite(10, TimeUnit.MINUTES) // TTL
+        .maximumSize(100)
+        .build();
+
+    @Override
+    public Authentication authenticate(Authentication authentication) throws AuthenticationException {
+        String username = (String) authentication.getPrincipal();
+        String apiPassword = (String) authentication.getCredentials();
+
+        if (Strings.isNullOrEmpty(username) || Strings.isNullOrEmpty(apiPassword)) {
+            throw new BadCredentialsException("Required parameters missing");
+        }
+
+        UserDetails userDetails = getFromCacheOrDatabase(username);
+        if (!areValuesSet(userDetails)) {
+            throw new DisabledException("The user does not exist, exists but is disabled or has API access disabled.");
+        }
+
+        boolean match = passwordEncoder.matches(apiPassword, userDetails.getPassword());
+        if (!match) {
+            throw new BadCredentialsException("Invalid password");
+        }
+
+        return UsernamePasswordAuthenticationToken.authenticated(
+            authentication.getPrincipal(),
+            authentication.getCredentials(),
+            userDetails.getAuthorities()
+        );
+    }
+
+    @Override
+    public void commence(HttpServletRequest request,
+                         HttpServletResponse response,
+                         AuthenticationException authException) throws IOException, ServletException {
+        HttpStatus status = HttpStatus.UNAUTHORIZED;
+
+        var apiResponse = ApiControllerAdvice.createResponse(
+            request.getRequestURL().toString(),
+            status,
+            authException.getMessage()
+        );
+
+        response.setStatus(status.value());
+        response.setContentType(MediaType.APPLICATION_JSON_VALUE);
+        response.getWriter().print(jacksonObjectMapper.writeValueAsString(apiResponse));
+    }
+
+    private UserDetails getFromCacheOrDatabase(String username) {
+        try {
+            return userCache.get(username, () -> {
+                UserDetails user = webUserService.loadUserByUsernameForApi(username);
+                return (user == null) ? DUMMY_USER : user;
+            });
+        } catch (ExecutionException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private static boolean areValuesSet(UserDetails userDetails) {
+        if (userDetails == null || userDetails == DUMMY_USER) {
+            return false;
+        }
+        if (!userDetails.isEnabled()) {
+            return false;
+        }
+        if (Strings.isNullOrEmpty(userDetails.getPassword())) {
+            return false;
+        }
+        return true;
+    }
+
+}

src/main/java/de/rwth/idsg/steve/config/SecurityConfiguration.java

@@ -18,35 +18,19 @@
  */
 package de.rwth.idsg.steve.config;
 
-import com.fasterxml.jackson.databind.ObjectMapper;
-import com.google.common.base.Strings;
-import de.rwth.idsg.steve.web.api.ApiControllerAdvice;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.annotation.Order;
-import org.springframework.http.HttpStatus;
-import org.springframework.http.MediaType;
-import org.springframework.security.authentication.AuthenticationManager;
-import org.springframework.security.authentication.DisabledException;
 import org.springframework.security.config.annotation.web.builders.HttpSecurity;
 import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
 import org.springframework.security.config.http.SessionCreationPolicy;
-import org.springframework.security.core.Authentication;
-import org.springframework.security.core.AuthenticationException;
 import org.springframework.security.crypto.factory.PasswordEncoderFactories;
 import org.springframework.security.crypto.password.DelegatingPasswordEncoder;
 import org.springframework.security.crypto.password.PasswordEncoder;
-import org.springframework.security.web.AuthenticationEntryPoint;
 import org.springframework.security.web.SecurityFilterChain;
-import org.springframework.security.web.authentication.preauth.AbstractPreAuthenticatedProcessingFilter;
-
-import jakarta.servlet.ServletException;
-import jakarta.servlet.http.HttpServletRequest;
-import jakarta.servlet.http.HttpServletResponse;
-
-import java.io.IOException;
+import org.springframework.security.web.authentication.www.BasicAuthenticationFilter;
 
 import static de.rwth.idsg.steve.SteveConfiguration.CONFIG;
 
@@ -105,88 +89,12 @@ public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Excepti
 
     @Bean
     @Order(1)
-    public SecurityFilterChain apiKeyFilterChain(HttpSecurity http, ObjectMapper jacksonObjectMapper) throws Exception {
+    public SecurityFilterChain apiKeyFilterChain(HttpSecurity http, ApiAuthenticationManager apiAuthenticationManager) throws Exception {
         return http.securityMatcher(CONFIG.getApiMapping() + "/**")
             .csrf(k -> k.disable())
             .sessionManagement(k -> k.sessionCreationPolicy(SessionCreationPolicy.STATELESS))
-            .addFilter(new ApiKeyFilter())
+            .addFilter(new BasicAuthenticationFilter(apiAuthenticationManager, apiAuthenticationManager))
             .authorizeHttpRequests(k -> k.anyRequest().authenticated())
-            .exceptionHandling(k -> k.authenticationEntryPoint(new ApiKeyAuthenticationEntryPoint(jacksonObjectMapper)))
             .build();
     }
-
-    /**
-     * Enable Web APIs only if both properties for API key are set. This has two consequences:
-     * 1) Backwards compatibility: Existing installations with older properties file, that does not include these two
-     * new keys, will not expose the APIs. Every call will be blocked by default.
-     * 2) If you want to expose your APIs, you MUST set these properties. This action activates authentication (i.e.
-     * APIs without authentication are not possible, and this is a good thing).
-     */
-    public static class ApiKeyFilter extends AbstractPreAuthenticatedProcessingFilter implements AuthenticationManager {
-
-        private final String headerKey;
-        private final String headerValue;
-        private final boolean isApiEnabled;
-
-        public ApiKeyFilter() {
-            setAuthenticationManager(this);
-
-            headerKey = CONFIG.getWebApi().getHeaderKey();
-            headerValue = CONFIG.getWebApi().getHeaderValue();
-            isApiEnabled = !Strings.isNullOrEmpty(headerKey) && !Strings.isNullOrEmpty(headerValue);
-
-            if (!isApiEnabled) {
-                log.warn("Web APIs will not be exposed. Reason: 'webapi.key' and 'webapi.value' are not set in config file");
-            }
-        }
-
-        @Override
-        protected Object getPreAuthenticatedPrincipal(HttpServletRequest request) {
-            if (!isApiEnabled) {
-                throw new DisabledException("Web APIs are not exposed");
-            }
-            return request.getHeader(headerKey);
-        }
-
-        @Override
-        protected Object getPreAuthenticatedCredentials(HttpServletRequest request) {
-            return null;
-        }
-
-        @Override
-        public Authentication authenticate(Authentication authentication) throws AuthenticationException {
-            if (!isApiEnabled) {
-                throw new DisabledException("Web APIs are not exposed");
-            }
-
-            String principal = (String) authentication.getPrincipal();
-            authentication.setAuthenticated(headerValue.equals(principal));
-            return authentication;
-        }
-    }
-
-    public static class ApiKeyAuthenticationEntryPoint implements AuthenticationEntryPoint {
-
-        private final ObjectMapper mapper;
-
-        private ApiKeyAuthenticationEntryPoint(ObjectMapper mapper) {
-            this.mapper = mapper;
-        }
-
-        @Override
-        public void commence(HttpServletRequest request, HttpServletResponse response,
-                             AuthenticationException authException) throws IOException, ServletException {
-            HttpStatus status = HttpStatus.UNAUTHORIZED;
-
-            var apiResponse = ApiControllerAdvice.createResponse(
-                request.getRequestURL().toString(),
-                status,
-                "Full authentication is required to access this resource"
-            );
-
-            response.setStatus(status.value());
-            response.setContentType(MediaType.APPLICATION_JSON_VALUE);
-            response.getWriter().print(mapper.writeValueAsString(apiResponse));
-        }
-    }
 }

src/main/java/de/rwth/idsg/steve/service/WebUserService.java

@@ -63,6 +63,11 @@ public class WebUserService implements UserDetailsManager {
 
     @EventListener
     public void afterStart(ContextRefreshedEvent event) {
+        moveUserFromConfigToDatabase();
+        moveApiTokenFromConfigToDatabase();
+    }
+
+    private void moveUserFromConfigToDatabase() {
         if (this.hasUserWithAuthority("ADMIN")) {
             return;
         }
@@ -77,6 +82,10 @@ public void afterStart(ContextRefreshedEvent event) {
         this.createUser(user);
     }
 
+    private void moveApiTokenFromConfigToDatabase() {
+        // TODO
+    }
+
     @Override
     public void createUser(UserDetails user) {
         validateUserDetails(user);
@@ -140,6 +149,26 @@ public UserDetails loadUserByUsername(String username) throws UsernameNotFoundEx
             .build();
     }
 
+    public UserDetails loadUserByUsernameForApi(String username) {
+        WebUserRecord record = webUserRepository.loadUserByUsername(username);
+        if (record == null) {
+            return null;
+        }
+
+        // the builder User.password(..) does not allow null values
+        String apiPassword = record.getApiToken();
+        if (apiPassword == null) {
+            apiPassword = "";
+        }
+
+        return User
+            .withUsername(record.getUsername())
+            .password(apiPassword)
+            .disabled(!record.getEnabled())
+            .authorities(fromJson(record.getAuthorities()))
+            .build();
+    }
+
     public void deleteUser(int webUserPk) {
         webUserRepository.deleteUser(webUserPk);
     }