OpenSSL Bindings for Java

This project provides OpenSSL bindings for Java. As much as possible they attempt to use existing JSSE API's, so the SSLContext should be usable as a drop in replacement for applications that are currently using JSSE.

This code was originally based on the Tomcat Native code, however it has been fairly extensively modified to more closely align with JSSE and to support dynamic linking.

Usage

Maven artifact

There are two Maven artifacts to choose between, which one you use will depend on your use case:

    <dependency>
        <groupId>org.wildfly.openssl</groupId>
        <artifactId>wildfly-openssl-java</artifactId>
        <version>${project.version}</version>
    </dependency>
    
    <dependency>
        <groupId>org.wildfly.openssl</groupId>
        <artifactId>wildfly-openssl</artifactId>
        <version>${project.version}</version>
    </dependency>

The wildfly-openssl-java artifact does not contain any native code. To use it you will need to either place the native library somewhere that it can be found by System.loadLibrary, or include a maven artifact that has the library packaged (such as one of the platform specific artifacts built by this project).

The wildfly-openssl artifact contains binaries for Mac, Linux and Windows (all for x86_64). If no other version of these native libraries is found then these will be extracted to a temporary directory and loaded. This should allow it to run without having to worry about how to deal with the native code.

Registering the provider

These bindings are implemented as a security provider. By default the provider will not be installed, so the easiest way to install the provider is to call org.wildfly.openssl.OpenSSLProvider.register().

Note that at the moment this project does not provide signed jars (this may change in the future). If you wish to register this as a default provider you will need to sign the jar yourself.

Installing the native library

If you are running on x86_64 Mac, Windows or Linux then you can use the out of the box support provided by the wildfly-openssl artifact.

There are two different native libraries that must be loaded, the libwfssl binary provided by this project, and OpenSSL itself. libwfssl is loaded through a standard java.lang.System.loadLibrary() invocation, so should be located somewhere where it can be discovered by the JVM. Alternatively you can specify the org.wildfly.openssl.libwfssl.path system property to specify the full path to the libwfssl library.

OpenSSL is loaded dynamically, and its location can be specified by the org.wildfly.openssl.path system property. If this property is not present the standard system library search path with be used instead. Because the library is loaded dynamically it should be possible to use different versions of OpenSSL without needed to recompile.

Using the provider

After the provider has been registered all that is necessary to use it to get the SSLContext:

SSLContext sslContext =  SSLContext.getInstance("openssl.TLS");

The SSLContext can then be used as normal, and should provide a drop in replacement for JSSE.

Building

The java side of the project uses maven and can be build as normal (mvn install). The native code should be build as part of the standard build process.

Windows

To do the Windows build you need to run the build from a visual studio native tools command prompt. If you want to build the 32 bit natives you must use the 32 bit prompt (and have JAVA_HOME pointed to a 32 bit JVM), otherwise both the prompt and the JVM must be 64 bit.

Configuring Your Environment

1. Visit the OpenSSL Wiki and choose where to download OpenSSL from.

   • Install OpenSSL, ideally both 32 and 64 bit versions.
     • When prompted install the executables in the C:\OpenSSL-32\bin and C:\OpenSSL-64\bin directories respectively.
   • Optional: Configure a OPENSSL_32 and OPENSSL_64 permanent environment variable.

2. Next ensure you have both a 32 and 64 bit JDK installed.

   • You can download OpenJDK from Red Hat
   • It seems to be easiest to download the zips.
     • For example unzip to %USERPROFILE%\apps and rename the directory to something simple like java-1.8.0.

3. Download and install Visual Studio.

   • Make sure you install the native tools for the command prompt too.

Building 32-bit Natives

Navigate to the x86 Native Tools Command Prompt for VS 2019 executable. Generally you can navigate to this through the start menu. For Visual Studio 2019 Community the location is C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Visual Studio 2019\Visual Studio Tools\VC.

Once the command prompt is open make sure you set your JAVA_HOME to the 32-bit JDK. Then update the INCLUDE environment variable to include the OpenSSL headers.

Example:

cd %USERPROFILE%\projects\wildfly-openssl
set "JAVA_HOME=%USERPROFILE%\apps\java-1.8.0-32"
set "INCLUDE=%INCLUDE%;%OPENSSL_32%\include"
mvn clean install

Building 64-bit Natives

Navigate to the x64 Native Tools Command Prompt for VS 2019 executable. Generally you can navigate to this through the start menu. For Visual Studio 2019 Community the location is C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Visual Studio 2019\Visual Studio Tools\VC.

Once the command prompt is open make sure you set your JAVA_HOME to the 64-bit JDK. Then update the INCLUDE environment variable to include the OpenSSL headers.

Example:

cd %USERPROFILE%\projects\wildfly-openssl
set "JAVA_HOME=%USERPROFILE%\apps\java-1.8.0"
set "INCLUDE=%INCLUDE%;%OPENSSL_64%\include"
mvn clean install