org.jooby.handlers.CsrfHandler Maven / Gradle / Ivy
/**
* Apache License
* Version 2.0, January 2004
* http://www.apache.org/licenses/
*
* TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
*
* 1. Definitions.
*
* "License" shall mean the terms and conditions for use, reproduction,
* and distribution as defined by Sections 1 through 9 of this document.
*
* "Licensor" shall mean the copyright owner or entity authorized by
* the copyright owner that is granting the License.
*
* "Legal Entity" shall mean the union of the acting entity and all
* other entities that control, are controlled by, or are under common
* control with that entity. For the purposes of this definition,
* "control" means (i) the power, direct or indirect, to cause the
* direction or management of such entity, whether by contract or
* otherwise, or (ii) ownership of fifty percent (50%) or more of the
* outstanding shares, or (iii) beneficial ownership of such entity.
*
* "You" (or "Your") shall mean an individual or Legal Entity
* exercising permissions granted by this License.
*
* "Source" form shall mean the preferred form for making modifications,
* including but not limited to software source code, documentation
* source, and configuration files.
*
* "Object" form shall mean any form resulting from mechanical
* transformation or translation of a Source form, including but
* not limited to compiled object code, generated documentation,
* and conversions to other media types.
*
* "Work" shall mean the work of authorship, whether in Source or
* Object form, made available under the License, as indicated by a
* copyright notice that is included in or attached to the work
* (an example is provided in the Appendix below).
*
* "Derivative Works" shall mean any work, whether in Source or Object
* form, that is based on (or derived from) the Work and for which the
* editorial revisions, annotations, elaborations, or other modifications
* represent, as a whole, an original work of authorship. For the purposes
* of this License, Derivative Works shall not include works that remain
* separable from, or merely link (or bind by name) to the interfaces of,
* the Work and Derivative Works thereof.
*
* "Contribution" shall mean any work of authorship, including
* the original version of the Work and any modifications or additions
* to that Work or Derivative Works thereof, that is intentionally
* submitted to Licensor for inclusion in the Work by the copyright owner
* or by an individual or Legal Entity authorized to submit on behalf of
* the copyright owner. For the purposes of this definition, "submitted"
* means any form of electronic, verbal, or written communication sent
* to the Licensor or its representatives, including but not limited to
* communication on electronic mailing lists, source code control systems,
* and issue tracking systems that are managed by, or on behalf of, the
* Licensor for the purpose of discussing and improving the Work, but
* excluding communication that is conspicuously marked or otherwise
* designated in writing by the copyright owner as "Not a Contribution."
*
* "Contributor" shall mean Licensor and any individual or Legal Entity
* on behalf of whom a Contribution has been received by Licensor and
* subsequently incorporated within the Work.
*
* 2. Grant of Copyright License. Subject to the terms and conditions of
* this License, each Contributor hereby grants to You a perpetual,
* worldwide, non-exclusive, no-charge, royalty-free, irrevocable
* copyright license to reproduce, prepare Derivative Works of,
* publicly display, publicly perform, sublicense, and distribute the
* Work and such Derivative Works in Source or Object form.
*
* 3. Grant of Patent License. Subject to the terms and conditions of
* this License, each Contributor hereby grants to You a perpetual,
* worldwide, non-exclusive, no-charge, royalty-free, irrevocable
* (except as stated in this section) patent license to make, have made,
* use, offer to sell, sell, import, and otherwise transfer the Work,
* where such license applies only to those patent claims licensable
* by such Contributor that are necessarily infringed by their
* Contribution(s) alone or by combination of their Contribution(s)
* with the Work to which such Contribution(s) was submitted. If You
* institute patent litigation against any entity (including a
* cross-claim or counterclaim in a lawsuit) alleging that the Work
* or a Contribution incorporated within the Work constitutes direct
* or contributory patent infringement, then any patent licenses
* granted to You under this License for that Work shall terminate
* as of the date such litigation is filed.
*
* 4. Redistribution. You may reproduce and distribute copies of the
* Work or Derivative Works thereof in any medium, with or without
* modifications, and in Source or Object form, provided that You
* meet the following conditions:
*
* (a) You must give any other recipients of the Work or
* Derivative Works a copy of this License; and
*
* (b) You must cause any modified files to carry prominent notices
* stating that You changed the files; and
*
* (c) You must retain, in the Source form of any Derivative Works
* that You distribute, all copyright, patent, trademark, and
* attribution notices from the Source form of the Work,
* excluding those notices that do not pertain to any part of
* the Derivative Works; and
*
* (d) If the Work includes a "NOTICE" text file as part of its
* distribution, then any Derivative Works that You distribute must
* include a readable copy of the attribution notices contained
* within such NOTICE file, excluding those notices that do not
* pertain to any part of the Derivative Works, in at least one
* of the following places: within a NOTICE text file distributed
* as part of the Derivative Works; within the Source form or
* documentation, if provided along with the Derivative Works; or,
* within a display generated by the Derivative Works, if and
* wherever such third-party notices normally appear. The contents
* of the NOTICE file are for informational purposes only and
* do not modify the License. You may add Your own attribution
* notices within Derivative Works that You distribute, alongside
* or as an addendum to the NOTICE text from the Work, provided
* that such additional attribution notices cannot be construed
* as modifying the License.
*
* You may add Your own copyright statement to Your modifications and
* may provide additional or different license terms and conditions
* for use, reproduction, or distribution of Your modifications, or
* for any such Derivative Works as a whole, provided Your use,
* reproduction, and distribution of the Work otherwise complies with
* the conditions stated in this License.
*
* 5. Submission of Contributions. Unless You explicitly state otherwise,
* any Contribution intentionally submitted for inclusion in the Work
* by You to the Licensor shall be under the terms and conditions of
* this License, without any additional terms or conditions.
* Notwithstanding the above, nothing herein shall supersede or modify
* the terms of any separate license agreement you may have executed
* with Licensor regarding such Contributions.
*
* 6. Trademarks. This License does not grant permission to use the trade
* names, trademarks, service marks, or product names of the Licensor,
* except as required for reasonable and customary use in describing the
* origin of the Work and reproducing the content of the NOTICE file.
*
* 7. Disclaimer of Warranty. Unless required by applicable law or
* agreed to in writing, Licensor provides the Work (and each
* Contributor provides its Contributions) on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied, including, without limitation, any warranties or conditions
* of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
* PARTICULAR PURPOSE. You are solely responsible for determining the
* appropriateness of using or redistributing the Work and assume any
* risks associated with Your exercise of permissions under this License.
*
* 8. Limitation of Liability. In no event and under no legal theory,
* whether in tort (including negligence), contract, or otherwise,
* unless required by applicable law (such as deliberate and grossly
* negligent acts) or agreed to in writing, shall any Contributor be
* liable to You for damages, including any direct, indirect, special,
* incidental, or consequential damages of any character arising as a
* result of this License or out of the use or inability to use the
* Work (including but not limited to damages for loss of goodwill,
* work stoppage, computer failure or malfunction, or any and all
* other commercial damages or losses), even if such Contributor
* has been advised of the possibility of such damages.
*
* 9. Accepting Warranty or Additional Liability. While redistributing
* the Work or Derivative Works thereof, You may choose to offer,
* and charge a fee for, acceptance of support, warranty, indemnity,
* or other liability obligations and/or rights consistent with this
* License. However, in accepting such obligations, You may act only
* on Your own behalf and on Your sole responsibility, not on behalf
* of any other Contributor, and only if You agree to indemnify,
* defend, and hold each Contributor harmless for any liability
* incurred by, or claims asserted against, such Contributor by reason
* of your accepting any such warranty or additional liability.
*
* END OF TERMS AND CONDITIONS
*
* APPENDIX: How to apply the Apache License to your work.
*
* To apply the Apache License to your work, attach the following
* boilerplate notice, with the fields enclosed by brackets "{}"
* replaced with your own identifying information. (Don't include
* the brackets!) The text should be enclosed in the appropriate
* comment syntax for the file format. We also recommend that a
* file or class name and description of purpose be included on the
* same "printed page" as the copyright notice for easier
* identification within third-party archives.
*
* Copyright 2014 Edgar Espina
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jooby.handlers;
import static java.util.Objects.requireNonNull;
import java.util.Set;
import java.util.UUID;
import java.util.function.Function;
import java.util.function.Predicate;
import org.jooby.Err;
import org.jooby.Request;
import org.jooby.Response;
import org.jooby.Route;
import org.jooby.Session;
import org.jooby.Status;
import com.google.common.collect.ImmutableSet;
/**
* Cross Site Request Forgery handler
*
*
* {
* use("*", new CsrfHandler());
* }
*
*
*
* This filter require a token on POST, PUT, PATCH and
* DELETE requests. A custom policy might be provided via:
* {@link #requireTokenOn(Predicate)}.
*
*
*
* Default token generator, use a {@link UUID#randomUUID()}. A custom token generator might be
* provided via: {@link #tokenGen(Function)}.
*
*
*
* Default token name is: csrf. If you want to use a different name, just pass the name
* to the {@link #CsrfHandler(String)} constructor.
*
*
* Token verification
*
* The {@link CsrfHandler} handler will read an existing token from {@link Session} (or created a
* new one
* is necessary) and make available as a request local variable via:
* {@link Request#set(String, Object)}.
*
*
*
* If the incoming request require a token verification, it will extract the token from:
*
*
* - HTTP header
* - HTTP parameter
*
*
*
* If the extracted token doesn't match the existing token (from {@link Session}) a 403
* will be thrown.
*
*
* @author edgar
* @since 0.8.1
*/
public class CsrfHandler implements Route.Filter {
private final Set REQUIRE_ON = ImmutableSet.of("POST", "PUT", "DELETE", "PATCH");
private String name;
private Function generator;
private Predicate requireToken;
/**
* Creates a new {@link CsrfHandler} handler and use the given name to save the token in the
* {@link Session} and or extract the token from incoming requests.
*
* @param name Token's name.
*/
public CsrfHandler(final String name) {
this.name = requireNonNull(name, "Name is required.");
tokenGen(req -> UUID.randomUUID().toString());
requireTokenOn(req -> REQUIRE_ON.contains(req.method()));
}
/**
* Creates a new {@link CsrfHandler} and use csrf as token name.
*/
public CsrfHandler() {
this("csrf");
}
/**
* Set a custom token generator. Default generator use: {@link UUID#randomUUID()}.
*
* @param generator A custom token generator.
* @return This filter.
*/
public CsrfHandler tokenGen(final Function generator) {
this.generator = requireNonNull(generator, "Generator is required.");
return this;
}
/**
* Decided whenever or not an incoming request require token verification. Default predicate
* requires verification on: POST, PUT, PATCH and
* DELETE requests.
*
* @param requireToken Predicate to use.
* @return This filter.
*/
public CsrfHandler requireTokenOn(final Predicate requireToken) {
this.requireToken = requireNonNull(requireToken, "RequireToken predicate is required.");
return this;
}
@Override
public void handle(final Request req, final Response rsp, final Route.Chain chain)
throws Throwable {
/**
* Get or generate a token
*/
Session session = req.session();
String token = session.get(name).toOptional().orElseGet(() -> {
String newToken = generator.apply(req);
session.set(name, newToken);
return newToken;
});
req.set(name, token);
if (requireToken.test(req)) {
String candidate = req.header(name).toOptional()
.orElseGet(() -> req.param(name).toOptional().orElse(null));
if (!token.equals(candidate)) {
throw new Err(Status.FORBIDDEN, "Invalid Csrf token: " + candidate);
}
}
chain.next(req, rsp);
}
}