Extract authorities from permissions claim (#40)

* Extract authorities from permissions claim

* Apply suggestions from code review

Co-Authored-By: Luciano Balmaceda <balmacedaluciano@gmail.com>

Co-authored-by: Luciano Balmaceda <balmacedaluciano@gmail.com>

Author: jimmyjames

.gitignore

@@ -88,3 +88,6 @@ gradle-app.setting
 # # Work around https://youtrack.jetbrains.com/issue/IDEA-116898
 # gradle/wrapper/gradle-wrapper.properties
 
+*.classpath
+*.project
+*.settings/

README.md

@@ -30,7 +30,7 @@ implementation 'com.auth0:auth0-spring-security-api:1.2.6'
 
 ## Usage
 
-Inside a `WebSecurityConfigurerAdapter` you can configure your API to only accept `RS256` signed JWTs
+Inside a `WebSecurityConfigurerAdapter` you can configure your API to only accept `RS256` signed JWTs:
 
 ```java
 @EnableWebSecurity
@@ -46,7 +46,7 @@ public class SecurityConfig extends WebSecurityConfigurerAdapter {
 }
 ```
 
-or for `HS256` signed JWTs
+or for `HS256` signed JWTs:
 
 ```java
 @EnableWebSecurity
@@ -65,20 +65,29 @@ public class SecurityConfig extends WebSecurityConfigurerAdapter {
 > If you need further customization (like a leeway for JWT verification) use the `JwtWebSecurityConfigurer` signatures which accept a `JwtAuthenticationProvider`.
 
 
-Then using Spring Security `HttpSecurity` you can specify which paths requires authentication
+Then using Spring Security `HttpSecurity` you can specify which paths requires authentication:
 
 ```java
     http.authorizeRequests()
         .antMatchers("/api/**").fullyAuthenticated();
 ```
 
-and you can even specify that the JWT should have a single or several scopes
+To restrict access based on the presence of a specific scope or permission claim, you can use the `hasAuthority` method.
+Scope and permissions claim values are prefixed with `SCOPE_` and `PERMISSION_`, respectively.
+
+To require a specific scope (`read:users` in the example below):
 
 ```java
     http.authorizeRequests()
-        .antMatchers(HttpMethod.GET, "/api/users/**").hasAuthority("read:users");
+        .antMatchers(HttpMethod.GET, "/api/users/**").hasAuthority("SCOPE_read:users");
 ```
 
+To require a specific permission (`admin` in the example below):
+
+```java
+    http.authorizeRequests()
+        .antMatchers(HttpMethod.GET, "/api/admin/**").hasAuthority("PERMISSION_admin");
+```
 
 `JwtWebSecurityConfigurer#configure(HttpSecurity)` also returns `HttpSecurity` so you can do the following:
 
@@ -93,7 +102,8 @@ public class SecurityConfig extends WebSecurityConfigurerAdapter {
                 .forRS256("YOUR_API_AUDIENCE", "YOUR_API_ISSUER")
                 .configure(http)
                 .authorizeRequests()
-                        .antMatchers(HttpMethod.GET, "/api/users/**").hasAuthority("read:users");
+                        .antMatchers(HttpMethod.GET, "/api/users/**").hasAuthority("SCOPE_read:users")
+                        .antMatchers(HttpMethod.GET, "/api/admin/**").hasAuthority("PERMISSION_admin");
     }
 }
 ```

lib/src/main/java/com/auth0/spring/security/api/authentication/AuthenticationJsonWebToken.java

@@ -8,12 +8,13 @@
 import org.springframework.security.core.GrantedAuthority;
 import org.springframework.security.core.authority.SimpleGrantedAuthority;
 
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.List;
+import java.util.*;
 
 public class AuthenticationJsonWebToken implements Authentication, JwtAuthentication {
 
+    private final static String SCOPE_AUTHORITY_PREFIX = "SCOPE_";
+    private final static String PERMISSION_AUTHORITY_PREFIX = "PERMISSION_";
+
     private final DecodedJWT decoded;
     private boolean authenticated;
 
@@ -39,15 +40,13 @@ public Authentication verify(JWTVerifier verifier) throws JWTVerificationExcepti
 
     @Override
     public Collection<? extends GrantedAuthority> getAuthorities() {
-        String scope = decoded.getClaim("scope").asString();
-        if (scope == null || scope.trim().isEmpty()) {
-            return new ArrayList<>();
-        }
-        final String[] scopes = scope.split(" ");
-        List<SimpleGrantedAuthority> authorities = new ArrayList<>(scopes.length);
-        for (String value : scopes) {
-            authorities.add(new SimpleGrantedAuthority(value));
-        }
+        List<SimpleGrantedAuthority> scopes = getScopeAuthorities();
+        List<SimpleGrantedAuthority> permissions = getPermissionAuthorities();
+
+        List<GrantedAuthority> authorities = new ArrayList<>();
+        authorities.addAll(scopes);
+        authorities.addAll(permissions);
+
         return authorities;
     }
 
@@ -83,4 +82,34 @@ public void setAuthenticated(boolean isAuthenticated) throws IllegalArgumentExce
     public String getName() {
         return decoded.getSubject();
     }
+
+    private List<SimpleGrantedAuthority> getScopeAuthorities() {
+        String scope = decoded.getClaim("scope").asString();
+        if (scope == null || scope.trim().isEmpty()) {
+            return Collections.emptyList();
+        }
+        final String[] scopes = scope.split(" ");
+        List<SimpleGrantedAuthority> authorities = new ArrayList<>(scopes.length * 2);
+        for (String value : scopes) {
+            // For backwards-compatibility, create authority without scope prefix
+            authorities.add(new SimpleGrantedAuthority(value));
+            authorities.add(new SimpleGrantedAuthority(SCOPE_AUTHORITY_PREFIX + value));
+        }
+        return authorities;
+    }
+
+    private List<SimpleGrantedAuthority> getPermissionAuthorities() {
+        String[] permissions = decoded.getClaim("permissions").asArray(String.class);
+
+        if (permissions == null || permissions.length == 0) {
+            return Collections.emptyList();
+        }
+
+        List<SimpleGrantedAuthority> authorities = new ArrayList<>(permissions.length);
+        for (String value : permissions) {
+            authorities.add(new SimpleGrantedAuthority(PERMISSION_AUTHORITY_PREFIX + value));
+        }
+
+        return authorities;
+    }
 }

lib/src/test/java/com/auth0/spring/security/api/authentication/AuthenticationJsonWebTokenTest.java

@@ -4,7 +4,6 @@
 import com.auth0.jwt.JWTVerifier;
 import com.auth0.jwt.algorithms.Algorithm;
 import com.auth0.jwt.interfaces.DecodedJWT;
-import com.auth0.spring.security.api.authentication.AuthenticationJsonWebToken;
 import org.hamcrest.Matchers;
 import org.hamcrest.collection.IsCollectionWithSize;
 import org.hamcrest.collection.IsEmptyCollection;
@@ -15,6 +14,7 @@
 import org.springframework.security.core.GrantedAuthority;
 
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.Map;
 
@@ -206,15 +206,49 @@ public void shouldGetScopeAsAuthorities() throws Exception {
                 .withClaim("scope", "auth0 auth10")
                 .sign(hmacAlgorithm);
 
+        AuthenticationJsonWebToken auth = new AuthenticationJsonWebToken(token, verifier);
+        assertThat(auth, is(notNullValue()));
+
+        Collection<? extends GrantedAuthority> authorities = auth.getAuthorities();
+        assertThat(authorities, is(notNullValue()));
+        assertThat(authorities, is(IsCollectionWithSize.hasSize(4)));
+        assertThat(authorities, containsInAnyOrder(
+                hasProperty("authority", is("auth0")),
+                hasProperty("authority", is("auth10")),
+                hasProperty("authority", is("SCOPE_auth0")),
+                hasProperty("authority", is("SCOPE_auth10"))
+        ));
+    }
+
+    @Test
+    public void shouldGetEmptyAuthoritiesOnEmptyPermissionsClaim() throws Exception {
+        String token = JWT.create()
+                .withArrayClaim("permissions", new String[]{})
+                .sign(hmacAlgorithm);
+
+        AuthenticationJsonWebToken auth = new AuthenticationJsonWebToken(token, verifier);
+        assertThat(auth, is(notNullValue()));
+        assertThat(auth.getAuthorities(), is(notNullValue()));
+        assertThat(auth.getAuthorities(), is(IsEmptyCollection.empty()));
+    }
+
+    @Test
+    public void shouldGetPermissionsAsAuthorities() throws Exception {
+        String[] permissionsClaim = {"read:permission", "write:permission"};
+        String token = JWT.create()
+                .withArrayClaim("permissions", permissionsClaim)
+                .sign(hmacAlgorithm);
+
         AuthenticationJsonWebToken auth = new AuthenticationJsonWebToken(token, verifier);
         assertThat(auth, is(notNullValue()));
         assertThat(auth.getAuthorities(), is(notNullValue()));
         assertThat(auth.getAuthorities(), is(IsCollectionWithSize.hasSize(2)));
 
-        ArrayList<GrantedAuthority> authorities = new ArrayList<>(auth.getAuthorities());
-        assertThat(authorities.get(0), is(notNullValue()));
-        assertThat(authorities.get(0).getAuthority(), is("auth0"));
-        assertThat(authorities.get(1), is(notNullValue()));
-        assertThat(authorities.get(1).getAuthority(), is("auth10"));
+        Collection<? extends GrantedAuthority> authorities = auth.getAuthorities();
+        assertThat(authorities, IsCollectionWithSize.hasSize(2));
+        assertThat(authorities, containsInAnyOrder(
+                hasProperty("authority", is("PERMISSION_" + permissionsClaim[0])),
+                hasProperty("authority", is("PERMISSION_" + permissionsClaim[1]))
+        ));
     }
 }