diff --git a/extensions/guacamole-auth-openid/src/main/java/org/apache/guacamole/auth/oauth/form/OAuthTokenField.java b/extensions/guacamole-auth-openid/src/main/java/org/apache/guacamole/auth/oauth/form/OAuthTokenField.java index 84484e5e8..5d6599fc4 100644 --- a/extensions/guacamole-auth-openid/src/main/java/org/apache/guacamole/auth/oauth/form/OAuthTokenField.java +++ b/extensions/guacamole-auth-openid/src/main/java/org/apache/guacamole/auth/oauth/form/OAuthTokenField.java @@ -20,8 +20,9 @@ package org.apache.guacamole.auth.oauth.form; import java.io.UnsupportedEncodingException; +import java.math.BigInteger; import java.net.URLEncoder; -import java.util.UUID; +import java.security.SecureRandom; import org.apache.guacamole.form.Field; /** @@ -42,6 +43,23 @@ public class OAuthTokenField extends Field { */ private final String authorizationURI; + /** + * Cryptographically-secure random number generator for generating the + * required nonce. + */ + private static final SecureRandom random = new SecureRandom(); + + /** + * Generates a cryptographically-secure nonce value. The nonce is intended + * to be used to prevent replay attacks. + * + * @return + * A cryptographically-secure nonce value. + */ + private static String generateNonce() { + return new BigInteger(130, random).toString(32); + } + /** * Creates a new OAuth "id_token" field which links to the given OAuth * service using the provided client ID. Successful authentication at the @@ -76,7 +94,7 @@ public class OAuthTokenField extends Field { + "&response_type=id_token" + "&client_id=" + URLEncoder.encode(clientID, "UTF-8") + "&redirect_uri=" + URLEncoder.encode(redirectURI, "UTF-8") - + "&nonce=" + UUID.randomUUID().toString(); + + "&nonce=" + generateNonce(); } // Java is required to provide UTF-8 support