WSS4R

Project home: www.rubyforge.org/projects/wss4r Author : Roland Schmitt, [email protected] Date : 01.02.2006

Version : 0.3

1. What is it (and what is it not)
2. Requirements
3. Installation
4. Usage
  4.1. Resolver

4.2. UsernameToken 4.3. Encryption 4.4. Signature 4.5. Signature/Encryption

4.6. Interoperability with WSE 2.0

4.7. Interoperability with JWSDP 2.0 4.8. Integration into rails

5. Samples
  5.1. A simple example

5.2. Rails example

6. License
7. Support
8. URLs

1. What is it (and what is it not)

WSS4R (Web Service Security For Ruby) is a library that implements some of the 
standards for web service security defined by the oasis open consortium [1].
It is a proof of concept (or "Can i do it with ruby?") and not an fully featured
implementation, so it's focussed on the encryption and signature aspects of 
web services. WSS4R sits on top of the famous soap4r library of NAKAMURA Hiroshi [2],
so implementing servers or clients that uses data encryption or signatures is easy
when you know how to use soap4r. 
Besides that there is a integration into the rails [3] application server, so you
can use the features of WSS4R in rails driven web services.
I've tested WSS4R with the following counterparts:
   - Web Service Enhancements 2.0 [8]

- Java Web Service Development Pack 2.0 [9]

WSS4R is my first ruby project, so it is not very ruby like in most places nor is it
a example of good ruby programming in general. It was started mostly to learn ruby, 
not to implement an full featured WS-Security conform library.
If you like it or hate it or want more features, drop me an email at [email protected].

2. Requirements

- Ruby [4] with compiled bindings to openssl [6]

(tested only with Ruby 1.8.4) - soap4r [2] (tested with soap4r version from 04. Dez. 2005), - Log4r [5] (tested with version 1.0.5) Optional (for the examples): - Rails [3] (tested with version 1.0.0) - Sqlite3-Ruby [7]

(tested with version 1.1.0)

3. Installation

Simly do

ruby setup.rb

4. Usage

To use WSS4R, one have to require the new driver class

require “wss4r/rpc/driver” instead of require “soap/rpc/driver”

4.1. Resolver

Resolver objects are used to find certificates, keys and to authenticate users. Resolver objects know how to get the corresponding private key for a certificate or how to load a certificate identified by a name. For example, when a client sends a encrypted request to the server, there is only the certificate embedded in the message. A resolver object is responsible for loading the private key of the certificate. There two implementations of resolvers: - CertificateDirectoryResolver Loads keys/certificates from files in a specified directory in the file system.

- DatabaseResolver Loads keys/certificates from sqlite3 databases.

4.2. UsernameToken

Example: … driver = Driver.new(‘localhost:8070/’,‘urn:multiply’) driver.add_method(‘multiply’,‘a’,‘b’)

...

usernametoken = UsernameToken.new(“username”, “password”) driver.security().add_security_token(usernametoken) … The client is authenticated with his username and password. The password is not sended as clear text, instead a hash function is used.

4.3. Encryption

Example: … resolver = CertificateDirectoryResolver.new(“../certs/ca”) certificate = resolver.certificate_by_subject(“/C=DE/ST=Rheinland-Pfalz/L=Trier/O=FF/OU=Development/CN=Server/[email protected]”) x509 = X509SecurityToken.new(certificate) enc_data = EncryptedData.new(x509) driver.security().add_security_token(enc_data) … The soap body is encrypted with the TripleDES algorithm. The used encryption key is then encrypted with the certificates public key and placed in the soap header. Actually only TripleDES and AES are supported by WSS4R as encryption algorithms. To use AES instead of the default TripleDES, set: enc_data.sessionkey_algorithm=(Types::ALGORITHM_AES_CBC)

4.4. Signature

Example:

… sign_cert = OpenSSL::X509::Certificate.new(File.read(“../certs/wse/wse-client.cer”)) pkey = OpenSSL::PKey::RSA.new(File.read(“../certs/wse/wse-client.key”)) x509 = X509SecurityToken.new(sign_cert, pkey) signature = Signature.new(x509) driver.security().add_security_token(signature) … The soap body and the soap header timestamp elements are signed with the supplied certificate. The signature is embedded in the soap header.

4.5. Signature/Encryption

Example:

…

		 resolver = CertificateDirectoryResolver.new("../certs/wse")

driver.security().add_security_resolver(resolver) sign_cert = OpenSSL::X509::Certificate.new(File.read(“../certs/wse/wse-client.cer”)) pkey = OpenSSL::PKey::RSA.new(File.read(“../certs/wse/wse-client.key”)) x509 = X509SecurityToken.new(sign_cert, pkey) signature = Signature.new(x509) driver.security().add_security_token(signature)

encrypt_cert = OpenSSL::X509::Certificate.new(File.read("../certs/wse/wse-server.cer"))

x509 = X509SecurityToken.new(encrypt_cert) enc_data = EncryptedData.new(x509) enc_data.sessionkey_algorithm=(Types::ALGORITHM_AES_CBC) driver.security().add_security_token(enc_data) …

You can combine signature and encryption. In most cases, for encryption the clients certificate is used and

for signature the certificate of the server. If you first apply the encryption, the signature is generated over the encrypted data. When signing is the first step, the the signature is generated from the plain content. So it is important to know which token is first added to the driver object.

4.6. Interoperability with WSE 2.0

Should work with usernames, encryption and signatures.

Sample Visual Studio projects are provided in examples/WebServiceTest (client) and examples/WebService (server).

4.7. Interoperability with JWSDP 2.0

Should work with usernames, encryption and signatures. Per default the examples the JWSDP works with keyIdendifiers for finding certificates and keys. WSS4R does not support the keyIdentifier mechanism to identify certificates, because it is not a standard.

4.8. Integration into rails

To use WSS4R in rails one have to modify the controller that implements the web service:

require “wss4r/aws/utils” require “activerecordresolver”

class SimpleServiceController < ApplicationController wsdl_service_name ‘SimpleService’

web_service_scaffold :invoke
web_service_api SimpleServiceApi
wss_add_resolvers([ActiveRecordResolver.new()])

I’ve only tested the direct dispatching mode of action web service with WSS4R.

5. Examples

All examples are placed in the examples subfolder.

certs Folder with various certificates and keys for the different examples |– ca Generated certificates and keys for the WSS4R examples |– jwsdp_15 Certificates and keys for to use with the JWSDP 1.5

|-- jwsdp_16      Certificates and keys for to use with the JWSDP 1.6/2.0
|-- wse           Certificates and keys for to use with the WSE 2.0

clients PlainNET.rb Example for using a .NET web service without web service security features. PlainXWS.rb Example for using a JWSDP web service without web service security features. TestNET.rb Example for using a WSE 2.0 web service. Shows usenametoken, encryption and signature. Client for the project in the WebService folder. TestXWS.rb Example for using a JWSDP 2.0 web service. Shows usenametoken, encryption and signature. Client for the examples bundled with the JWSDP 2.0 package. The service is found in %JWSDP_HOME%/xws-security/samples/simple. To work, set the the keyReferenceType in the JWSDP xml config files under config/ to “Direct”. TestWSS4R.rb Example for using a WSS4R/soap4r web service. Shows usenametoken, encryption and signature. Used with the server in the server folder.

rails |– simple Example for rails integration. Requires sqlite3-ruby. |– client Test client for the rails web service. |– app Files for the web service |– controllers Implementration of the web service and setup for the resolver, encryption and signing. |– helpers Resolver implementation that uses ActiveRecord to load certificates and keys. |– databases Sqlite3 database with certificates and keys.

server |– TestServer.rb WebRick server using soap4r and WSS4R.

WebService Visual Studio project for a WSE 2.0 enabled web service. Created with Visual Studio 2003 and C#. WebServiceTest Visual Studio project with clients for the WebService project and for the rails example. Created with Visual Studio 2003 and C#.

5.1. A simple example

At the command line, go to examples/server and type: ruby TestServer.rb user A WebRick server starts that requires a username/password from the client, where the password is the username reversed. In another shell, change the working dir to examples/clients and type: ruby TestWSS4R.rb user

It show the result of the multiplication of the 2 arguments. The client uses “Ron” as username and “noR” as password. Setting the password to other values than “noR” in the TestWSS4R.rb file results in a “User not authenticatd!” message. Stop the TestServer with CTRL-Z (or CTRL-C). Restart it with ruby TestServer.rb enc sign

The server now will first encrypt any request, then signing it. Start the client by typing: ruby TestClient.rb sign enc

The client first signs the request, then encrypts it and shows the response. You can use various monitoring tools like the tcpmon utility from the axis project [10] to view the resulting request/response messages.

5.2. Rails example

Go to examples/rails/simple and type
  ruby script/server

To start the client, open a new shell and go to examples/rails/simple/client.
  ruby client.rb

The output shows the reversed string that the client sents to the server. The client signs his request and the server encrypts
and signs the response.

6. License

WSS4R is licensed under GPL and Ruby’s custom license. See GPL and RUBYS.

7. Support

The RubyForge mailing list is at www.rubyforge.org/projects/wss4r.

Or, to contact the author, send mail to [email protected]

8. URLs

 [1] - http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=wss  
 [2] - http://dev.ctor.org/soap4r/
 [3] - http://www.rubyonrails.org
 [4] - http://www.ruby-lang.org
 [5] - http://log4r.sourceforge.net/
 [6] - http://www.openssl.org
 [7] - http://rubyforge.org/projects/sqlite-ruby/
 [8] - http://msdn.microsoft.com/webservices/webservices/building/wse/default.aspx
 [9] - https://jwsdp.dev.java.net/
[10] - http://ws.apache.org/axis/

WSS4R

Contents

1. What is it (and what is it not)

2. Requirements

3. Installation

4. Usage

4.1. Resolver

4.2. UsernameToken

4.3. Encryption

4.4. Signature

4.5. Signature/Encryption

4.6. Interoperability with WSE 2.0

4.7. Interoperability with JWSDP 2.0

4.8. Integration into rails

5. Examples

5.1. A simple example

5.2. Rails example

6. License

7. Support

8. URLs