Welcome!

Java IoT Authors: Liz McMillan, Pat Romanski, Elizabeth White, XebiaLabs Blog, Yeshim Deniz

Related Topics: Java IoT, IBM Cloud

Java IoT: Article

How to Create Secure Web Applications with Struts

Imagine building a house starting with only a pile of timber and a lump of iron

Imagine building a house starting with only a pile of timber and a lump of iron, or making a bowl of spaghetti from a sack of wheat and a bag of tomatoes. The importance of having the right materials makes the idea of building products from scratch seem absurd. Similarly, any software project that doesn't take advantage of the numerous frameworks available for any manner of development activity could be wasting valuable resources and ignoring established best practices.

The advantages of using frameworks are obvious to any developer who has implemented a complex, bug-ridden solution to a design problem that's already been elegantly addressed by a framework. And perhaps the most difficult design problems to get right are those concerning security. With the popularity of Web applications and services on the rise, there has been an increasing move to standardize security-critical tasks, such as authentication and session management, in the container or framework. This way, developers can focus on implementing business processes, rather than specialized tasks like cryptographic algorithms or pseudo-random number generation.

This article will focus on developing secure Web applications with the popular Java framework Struts. It will detail a set of best practices using the included security mechanisms. The first section will provide an overview of both Struts and Web application security as a context for discussion. Each subsequent section will focus on a specific security principle and discuss how Struts can be leveraged to address it.

Struts
Struts is a very popular framework for Java Web applications large and small because of the numerous advantages it offers developers. The main goal of the Struts framework is to enforce a MVC-style (Model-View-Controller) architecture, which means that there is a separation of concerns among different architectural components: the model is the representation of the logic, the view is in charge of displaying data to the user, and the controller is responsible for providing the user with a way to interact with the application and affect the model. A simple analogy for this is a video game, where you have a game console (the model), the television or monitor (the view), and a controller (quite appropriately, the controller). This architectural pattern promotes reuse and stability by reducing the effects of code changes (since the implementation of each component is agnostic to the implementation of the others and the model is isolated from the user).

Although it is approximately an implementation of the MVC pattern, Struts is more accurately based on the "Model 2" architecture specific to the Java servlet technology. Rather than having users access the JSPs directly, Struts applications have a "front controller" servlet that's the initial target of all requests and decides how to process requests and route users. Struts also has two different frameworks, the original (Struts Action Framework) and one based on JSF (Struts Shale). For the purposes of this article, we'll only consider the original framework.

Web Application Security
Web applications (such as those built on Struts) rely on users being able to access potentially sensitive information from all over the world over disparate untrusted networks. It's not exactly a surprise or a secret that many non-secure Web applications have been exploited, making front-page news and causing an enormous amount of problems for the organizations responsible. Application security attacks like SQL injection, cross-site scripting, session hijacking, and cookie poisoning are now mainstays in the toolkit of any hacker worth his salt, and it's becoming increasingly obvious that developers have to put more of an emphasis on security.

Organizations like OWASP (Open Web Application Security Project) and WASC (Web Application Security Consortium) have assembled a great deal of information on how to avoid common pitfalls and create more secure Web applications. These and other resources are invaluable for learning about Web application security, and this article complements them as a guide for best practices in Struts applications with respect to security. Here we'll focus on four specific types of security concerns and how they relate to Struts.

Struts & Input Validation
Input validation refers to the practice of verifying that input from an untrusted source is acceptable and safe to use. This has a significant security impact because malformed data submitted by a malicious user is the direct cause of numerous exploits (including SQL injection and cross-site scripting) and generally causes an application to behave unexpectedly and outside of its security design.

The Struts Validator plug-in lets you cleanly encapsulate all of your validation logic in XML configuration files instead of Java code. The Validator plug-in assists developers by standardizing common types of validations, preventing validation logic duplication, and being easier to verify and change (no recompilation is required). Two things to consider when using the Validator plug-in:

  1. There's a mechanism to validate the code of the ActionForm (org.apache.struts.action.ActionForm, the Java class in the controller responsible for handling user data). However, this doesn't offer the advantages described above and won't be discussed here.
  2. Any business-level validation should be performed in the model, and the controller should be limited to semantic validation (correct length, type, acceptable character set). For instance, in the Validator plug-in you might ensure a credit card number is the right format, but you'd ensure it's a valid card in the business logic.
Here's how the Validator plug-in works:

1.  User input is encapsulated in one of the ValidatorForm classes (which extend ActionForm classes):

public class UserValidatorForm extends org.apache.struts.validator.ValidatorForm {
      public String firstName;
      public String lastName;
      public String phoneNumber;
      public String userId;
      ...
}

2.  Validation functions (several standard ones come pre-baked) are defined in validator-rules.xml. This rule calls a validation method from a custom class:

<validator name="userId"
classname="com.jdjexample.validator.UserIdValidator"
method="validateUserId"
      methodParams="java.lang.Object,
      org.apache.commons.validator.ValidatorAction,
      org.apache.commons.validator.Field,
      org.apache.struts.action.ActionErrors,
      javax.servlet.http.HttpServletRequest"
    msg="errors.userid">
...
</validator>

3.  Validation.xml maps which fields have to be validated by which rules:

<form-validation>
  <formset>
     <form name="userForm">
       <field property="firstName" depends="required">
        <arg0 key="firstName.displayName"/>
      </field>
       <field property="lastName" depends="required ">
         <arg0 key="lastName.displayName"/>
       </field>
<field property="phoneNumber" depends="required, mask">
<arg0 key="phoneNumber.mask"/>
<var>
     <var-name>mask</var-name>
     <var-value>
     ^\D?(\d{3})\D?\D?(\d{3})\D?(\d{4})$
     </var-value>
</var>
</field>
</field>
     <field property="userId" depends="required, userId">
     <arg0 key="phoneNumber.mask"/>
     </field>
    </form>
   </formset>
</form-validation>

More Stories By Alex Smolen

Alex Smolen is a Software Security Consultant at Foundstone, where he provides security consulting services to clients to help find, fix, and prevent security vulnerabilities in enterprise software. His duties include threat modeling, code review, penetration testing and secure software development lifecycle (S-SDLC) design and implementation. Alex’s speaking engagements include Enterprise Architect Summit 2005 where he spoke on emerging trends in enterprise security as well as Better Software Conference 2005. Alex graduated from the University of California, Berkeley, with a BS in electrical engineering and computer science.

Comments (2) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Most Recent Comments
SYS-CON Belgium News Desk 03/19/06 01:48:20 PM EST

Imagine building a house starting with only a pile of timber and a lump of iron, or making a bowl of spaghetti from a sack of wheat and a bag of tomatoes. The importance of having the right materials makes the idea of building products from scratch seem absurd. Similarly, any software project that doesn't take advantage of the numerous frameworks available for any manner of development activity could be wasting valuable resources and ignoring established best practices.

SYS-CON India News Desk 03/19/06 10:15:48 AM EST

Imagine building a house starting with only a pile of timber and a lump of iron, or making a bowl of spaghetti from a sack of wheat and a bag of tomatoes. The importance of having the right materials makes the idea of building products from scratch seem absurd. Similarly, any software project that doesn't take advantage of the numerous frameworks available for any manner of development activity could be wasting valuable resources and ignoring established best practices.

@ThingsExpo Stories
Businesses and business units of all sizes can benefit from cloud computing, but many don't want the cost, performance and security concerns of public cloud nor the complexity of building their own private clouds. Today, some cloud vendors are using artificial intelligence (AI) to simplify cloud deployment and management. In his session at 20th Cloud Expo, Ajay Gulati, Co-founder and CEO of ZeroStack, will discuss how AI can simplify cloud operations. He will cover the following topics: why clou...
"Dice has been around for the last 20 years. We have been helping tech professionals find new jobs and career opportunities," explained Manish Dixit, VP of Product and Engineering at Dice, in this SYS-CON.tv interview at 19th Cloud Expo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
More and more brands have jumped on the IoT bandwagon. We have an excess of wearables – activity trackers, smartwatches, smart glasses and sneakers, and more that track seemingly endless datapoints. However, most consumers have no idea what “IoT” means. Creating more wearables that track data shouldn't be the aim of brands; delivering meaningful, tangible relevance to their users should be. We're in a period in which the IoT pendulum is still swinging. Initially, it swung toward "smart for smar...
The Internet of Things will challenge the status quo of how IT and development organizations operate. Or will it? Certainly the fog layer of IoT requires special insights about data ontology, security and transactional integrity. But the developmental challenges are the same: People, Process and Platform and how we integrate our thinking to solve complicated problems. In his session at 19th Cloud Expo, Craig Sproule, CEO of Metavine, demonstrated how to move beyond today's coding paradigm and sh...
We are always online. We access our data, our finances, work, and various services on the Internet. But we live in a congested world of information in which the roads were built two decades ago. The quest for better, faster Internet routing has been around for a decade, but nobody solved this problem. We’ve seen band-aid approaches like CDNs that attack a niche's slice of static content part of the Internet, but that’s it. It does not address the dynamic services-based Internet of today. It does...
In his keynote at 18th Cloud Expo, Andrew Keys, Co-Founder of ConsenSys Enterprise, provided an overview of the evolution of the Internet and the Database and the future of their combination – the Blockchain. Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life sett...
The WebRTC Summit New York, to be held June 6-8, 2017, at the Javits Center in New York City, NY, announces that its Call for Papers is now open. Topics include all aspects of improving IT delivery by eliminating waste through automated business models leveraging cloud technologies. WebRTC Summit is co-located with 20th International Cloud Expo and @ThingsExpo. WebRTC is the future of browser-to-browser communications, and continues to make inroads into the traditional, difficult, plug-in web ...
20th Cloud Expo, taking place June 6-8, 2017, at the Javits Center in New York City, NY, will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud strategy.
WebRTC is the future of browser-to-browser communications, and continues to make inroads into the traditional, difficult, plug-in web communications world. The 6th WebRTC Summit continues our tradition of delivering the latest and greatest presentations within the world of WebRTC. Topics include voice calling, video chat, P2P file sharing, and use cases that have already leveraged the power and convenience of WebRTC.
"We're a cybersecurity firm that specializes in engineering security solutions both at the software and hardware level. Security cannot be an after-the-fact afterthought, which is what it's become," stated Richard Blech, Chief Executive Officer at Secure Channels, in this SYS-CON.tv interview at @ThingsExpo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
The Internet of Things (IoT) promises to simplify and streamline our lives by automating routine tasks that distract us from our goals. This promise is based on the ubiquitous deployment of smart, connected devices that link everything from industrial control systems to automobiles to refrigerators. Unfortunately, comparatively few of the devices currently deployed have been developed with an eye toward security, and as the DDoS attacks of late October 2016 have demonstrated, this oversight can ...
Fact is, enterprises have significant legacy voice infrastructure that’s costly to replace with pure IP solutions. How can we bring this analog infrastructure into our shiny new cloud applications? There are proven methods to bind both legacy voice applications and traditional PSTN audio into cloud-based applications and services at a carrier scale. Some of the most successful implementations leverage WebRTC, WebSockets, SIP and other open source technologies. In his session at @ThingsExpo, Da...
Internet-of-Things discussions can end up either going down the consumer gadget rabbit hole or focused on the sort of data logging that industrial manufacturers have been doing forever. However, in fact, companies today are already using IoT data both to optimize their operational technology and to improve the experience of customer interactions in novel ways. In his session at @ThingsExpo, Gordon Haff, Red Hat Technology Evangelist, will share examples from a wide range of industries – includin...
Unless your company can spend a lot of money on new technology, re-engineering your environment and hiring a comprehensive cybersecurity team, you will most likely move to the cloud or seek external service partnerships. In his session at 18th Cloud Expo, Darren Guccione, CEO of Keeper Security, revealed what you need to know when it comes to encryption in the cloud.
We're entering the post-smartphone era, where wearable gadgets from watches and fitness bands to glasses and health aids will power the next technological revolution. With mass adoption of wearable devices comes a new data ecosystem that must be protected. Wearables open new pathways that facilitate the tracking, sharing and storing of consumers’ personal health, location and daily activity data. Consumers have some idea of the data these devices capture, but most don’t realize how revealing and...
"We build IoT infrastructure products - when you have to integrate different devices, different systems and cloud you have to build an application to do that but we eliminate the need to build an application. Our products can integrate any device, any system, any cloud regardless of protocol," explained Peter Jung, Chief Product Officer at Pulzze Systems, in this SYS-CON.tv interview at @ThingsExpo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
In his general session at 19th Cloud Expo, Manish Dixit, VP of Product and Engineering at Dice, discussed how Dice leverages data insights and tools to help both tech professionals and recruiters better understand how skills relate to each other and which skills are in high demand using interactive visualizations and salary indicator tools to maximize earning potential. Manish Dixit is VP of Product and Engineering at Dice. As the leader of the Product, Engineering and Data Sciences team at D...
Data is the fuel that drives the machine learning algorithmic engines and ultimately provides the business value. In his session at 20th Cloud Expo, Ed Featherston, director/senior enterprise architect at Collaborative Consulting, will discuss the key considerations around quality, volume, timeliness, and pedigree that must be dealt with in order to properly fuel that engine.
In addition to all the benefits, IoT is also bringing new kind of customer experience challenges - cars that unlock themselves, thermostats turning houses into saunas and baby video monitors broadcasting over the internet. This list can only increase because while IoT services should be intuitive and simple to use, the delivery ecosystem is a myriad of potential problems as IoT explodes complexity. So finding a performance issue is like finding the proverbial needle in the haystack.
According to Forrester Research, every business will become either a digital predator or digital prey by 2020. To avoid demise, organizations must rapidly create new sources of value in their end-to-end customer experiences. True digital predators also must break down information and process silos and extend digital transformation initiatives to empower employees with the digital resources needed to win, serve, and retain customers.