Using Security in CORBA Applications

Writing a CORBA Application That Implements Security

This topic includes the following sections:

Using the Bootstrapping Mechanism

The Bootstrap object in the BEA Tuxedo CORBA environment has been enhanced so that users can specify that all communication to a given IIOP Listener/Handler be protected. The Bootstrap object supports corbaloc and corbalocs Uniform Resource Locator (URL) address formats to be used when specifying the location of the IIOP Listener/Handler. The type of security provided depends on the format of URL used to specify the location of the IIOP Listener/Handler.

As with the Host and Port address format, you use the URL address formats to specify the location of the IIOP Listener/Handler, but the bootstrapping process behaves differently. When using the corbaloc or corbalocs URL address format, the initial connection to the IIOP Listener/Handler is deferred until either:

Using the corbalocs URL address format indicates that the SSL protocol is used to protect at least the integrity of the connection between the principal and the IIOP Listener/Handler.

Table 9-1 highlights the differences between the two URL address formats.

Both the corbaloc and corbalocs URL address formats provide stringified object references that are easily manipulated in both TCP/IP and Domain Name System (DNS) environments. The corbaloc and corbalocs URL address formats contain a DNS-style host name or an IP address and port.

The URL address formats follow and extend the definition of object URLs adopted by the Object Management Group (OMG) as part of the Interoperable Naming Service submission. The BEA Tuxedo software also extends the URL format described in the OMG Interoperable Naming Service submission to support a secure form that is modeled after the URL for secure HTTP, as well as to support functionality in previous releases of the WebLogic Enterprise product.

Listing 9-1 contains examples of the new URL address formats.

corbaloc://555xyz.com:1024,corbaloc://555backup.com:1022,
corbaloc://555last.com:1999
corbalocs://555xyz.com:1024,(corbalocs://555backup.com:1022|corbalocs://555last.com:1999)
corbaloc://555xyz.com:1111
corbalocs://24.128.122.32:1011, corbalocs://24.128.122.34

As an enhancement to the URL syntax described in the OMG Interoperable Naming Service submission, the BEA Tuxedo product extends the syntax to support a list of multiple URLs, each with a different scheme. Listing 9-2 contains examples of specifying multiple URLs.

corbalocs://555xyz.com:1024,corbaloc://555xyz.com:1111
corbalocs://ctxobj.com:3434,corbalocs://mthd.com:3434,corbaloc://force.com:1111

In the examples in Listing 9-2, if the parser reaches the URL corbaloc://force.com:1111, it resets its internal state as if it had never attempted secure connections, and then begins attempting unprotected connections. This situation occurs if the client application has not set any SSL parameters on the Credentials object.

The following sections describe the behavior when using the different address formats of the Bootstrap object.

Using the Host and Port Address Format

If a CORBA client application uses the Host and Port address format of the Bootstrap object, the constructor method of the Bootstrap object constructs an object reference using the specified host name and port number. The invocation to the IIOP Listener/Handler is made without the protections offered by the SSL protocol.

The client application can still authenticate using password authentication. However, since the bootstrapping process is performed over an unprotected and unverified link, all communications are vulnerable to the following security attacks:

Using the corbaloc URL Address Format

By default, the invocation on the IIOP Listener/Handler is unprotected when using the corbaloc URL address format and password authentication. Therefore, all communications are vulnerable to the following security attacks:

You can protect the bootstrapping process when using the corbaloc URL address format by using the SecurityLevel2::PrincipalAuthenticator::authenticate() method, specifying that certificate authentication is to be used, and setting the invocation_methods_required method on the Credentials object.

BEA recommends that existing CORBA applications migrate to the corbaloc URL address format instead of using the Host and Port Address format.

Using the corbalocs URL Address Format

The corbalocs URL address format is the recommended format to use to ensure that communications between principals and the IIOP Listener/Handler are protected. The corbalocs URL address format functions in the same way as the corbaloc URL address format, except the SSL protocol is used to protect all communications with the IIOP Listener/Handler or the CORBA C++ ORB regardless of the type of authentication used.

When the defaults are used with the corbalocs URL address format, communications are vulnerable only to Denial of Service security attacks. Using the SSL protocol and certificate authentication guards against Sniffer, Tamper, and Replay attacks. In addition, the validation check of the host specified in the digital certificate guards against Man-in-the-Middle attacks.

To use the corbalocs URL address format, the IIOP Listener/Handler or the CORBA C++ ORB must be configured to enable the use of the SSL protocol. For more information about configuring the IIOP Listener/Handler or the CORBA C++ ORB for the SSL protocol, see Configuring the SSL Protocol on page 6-1.

Using Password Authentication

This section describes implementing password authentication in a CORBA applications.

The Security Sample Application

The Security sample application demonstrates password authentication. The Security sample application requires each student using the application to have an ID and a password. The Security sample application works in the following manner:

Figure 9-1 illustrates the Security sample application.

The source files for the Security sample application are located in the \samples\corba\university directory in the BEA Tuxedo software. For information about building and running the Security sample application, see the Guide to the CORBA University Sample Applications.

Writing the Client Application

When using password authentication, write client application code that does the following:

The SecurityLevel2::PrincipalAuthenticator interface is defined in the CORBAservices Security Service specification. This interface contains two methods that are used to accomplish the authentication of the principal. There are two methods because authentication of principals may require more than one step. The authenticate() method allows the caller to authenticate and optionally select attributes for the principal of this session.

The CORBA environment extends the PrincipalAuthenticator object with functionality to support similar security to that found in the ATMI environment in the BEA Tuxedo product. The enhanced functionality is provided by the Tobj::PrincipalAuthenticator interface.

The methods defined for the Tobj::PrincipalAuthenticator interface provide a focused, simplified form of the equivalent CORBA-defined interface. You can use either the CORBA-defined or the BEA Tuxedo extensions when developing a CORBA application.

The Tobj::PrincipalAuthenticator interface provides the same functionality as the SecurityLevel2::PrincipalAuthenticator interface. However, unlike the SecurityLevel2::PrincipalAuthenticator::authenticate() method, the logon() method of the Tobj::PrincipalAuthenticator interface does not return a Credentials object. As a result, CORBA applications that need to use more than one principal identity are required to call the Current::get_credentials() method immediately after the logon() method to retrieve the Credentials object as a result of the logon. Retrieval of the Credentials object directly after a logon method should be protected with serialized access.

The following sections contain C++ code examples that illustrate implementing password authentication. For a Visual Basic code example, see Automation Security Reference on page 16-1.

C++ Code Example That Uses the SecurityLevel2::PrincipalAuthenticator::authenticate() Method

Listing 9-3 contains C++ code that performs password authentication using the SecurityLevel2::PrincipalAuthenticator::authenticate()method.

...
//Create Bootstrap object
     Tobj_Bootstrap* bootstrap = new Tobj_Bootstrap(orb, 
                      corbalocs://sling.com:2143);

//Get SecurityCurrent object
CORBA::Object_var var_security_current_oref =   
     bootstrap.resolve_initial_references("SecurityCurrent");
SecurityLevel2::Current_var var_security_current_ref = 
     SecurityLevel2::Current::_narrow(var_security_current_oref.in());

//Get the PrincipalAuthenticator
SecurityLevel2::PrincipalAuthenticator_var var_principal_authenticator =
     var_security_current_oref->principal_authenticator();

const char * user_name = "john"
const char * client_name = "university";
char system_password[31] = {`\0'};
char user_password[31] = {`\0'};

Tobj::PrincipalAuthenticator_ptr var_bea_principal_authenticator =
		   Tobj::PrincipalAuthenticator::_narrow(var_bea_principal_authenticator.in());

//Determine the security level
Tobj::AuthType auth_type = var_bea_principal_authenticator->get_auth_type();
switch (auth_type)
{
   case Tobj::TOBJ_NOAUTH;
   break;

   case Tobj::TOBJ_SYSAUTH
   strcpy(system_password, "sys_pw");

   case Tobj::TOBJ_APPAUTH
    strcpy(system_password, "sys_pw");
    strcpy(user_password, "john_pw");
    break;
}
if (auth_type != Tobj::TOBJ_NOAUTH)

{
     SecurityLevel2::Credentials_var					             creds;
     Security::Opaque_var                        auth_data;
     Security::AttributeList_var                 privileges;
     Security::Opaque_var                        cont_data;
     Security::Opaque_var                        auth_spec_data;

var_bea_principalauthenticator->build_auth_data(user_name,
                                                client_name,
                                                system_password,
                                                user_password,
                                                NULL,
                                                auth_data,
                                                privileges);
Security::AuthenticationStatus status = 
      var_bea_principalauthenticator->authenticate(
                                                   Tobj::TuxedoSecurity,
                                                   user_name,
                                                   auth_data,
                                                   privileges,
                                                   creds,
                                                   cont_data, auth_spec_data);

if (status != Security::SecAuthSuccess)
 {
    //Failed authentication
    return;
 }
}

// Proceed with application
...

C++ Code Example That Uses the Tobj::PrincipalAuthenticator::logon() Method

Listing 9-4 contains C++ code that performs password authentication using the Tobj::PrincipalAuthenticator::logon()method.

...
CORBA::Object_var var_security_current_oref =   
     bootstrap.resolve_initial_references("SecurityCurrent");
SecurityLevel2::Current_var var_security_current_ref = 
     SecurityLevel2::Current::_narrow(var_security_current_oref.in());

//Get the PrincipalAuthenticator
SecurityLevel2::PrincipalAuthenticator_var var_principal_authenticator_oref =
     var_security_current_oref->principal_authenticator();

//Narrow the PrincipalAuthenticator
Tobj::PrincipalAuthenticator_var var_bea_principal_authenticator =
     Tobj::PrincipalAuthenticator::_narrow 
                                     var_principal_authenticator_oref.in());

const char * user_name = "john"
const char * client_name = "university";
char system_password[31] = {`\0'};
char user_password[31] = {`\0'};

//Determine the security level
Tobj::AuthType auth_type = var_bea_principal_authenticator->get_auth_type();
switch (auth_type)
{
   case Tobj::TOBJ_NOAUTH;
   break;

   case Tobj::TOBJ_SYSAUTH
   strcpy(system_password, "sys_pw");

   case Tobj::TOBJ_APPAUTH
    strcpy(system_password, "sys_pw");
    strcpy(user_password, "john_pw");
    break;
}
if (auth_type != Tobj::TOBJ_NOAUTH)

{
     SecurityLevel2::Credentials_var					             creds;
     Security::Opaque_var                        auth_data;
     Security::AttributeList_var                 privileges;
     Security::Opaque_var                        cont_data;
     Security::Opaque_var                        auth_spec_data;

//Determine the security level
Tobj::AuthType auth_type = var_bea_principal_authenticator->get_auth_type();
Security::AuthenticationStatus status = var_bea_principal_authenticator->logon(
                                                   user_name,
                                                   client_name,
                                                   system_password,
                                                   user_password,
                                                   0);

if (status != Security::SecAuthSuccess)
 {
    //Failed authentication
    return;
 }
}
// Proceed with application
...
// Log off
    						  try 
         {
           logoff();
         }
...

Using Certificate Authentication

This section describes implementing certificate authentication in CORBA applications.

The Secure Simpapp Sample Application

The Secure Simpapp sample application uses the existing Simpapp sample application and modifies the code and configuration files to support secure communications through the SSL protocol and certificate authentication.

The server application in the Secure Simpapp sample application provides an implementation of a CORBA object that has the following two methods:

The Simpapp sample application was modified in the following ways to support certificate authentication and the SSL protocol:

The source files for the C++ Secure Simpapp sample application are located in the \samples\corba\simpappSSL directory of the BEA Tuxedo software. For instructions for building and running the Secure Simpapp sample application, see Building and Running the CORBA Sample Applications on page 10-1.

Writing the CORBA Client Application

When using certificate authentication, write CORBA client application code that does the following:

The following sections contain C++ code examples that illustrate implementing certificate authentication.

C++ Code Example of Certificate Authentication

Listing 9-5 illustrates using certificate authentication in a CORBA C++ client application.

....

// Initialize the ORB
CORBA::ORB_var v_orb = CORBA::ORB_init(argc, argv, "");

// Create the bootstrap object
Tobj_Bootstrap bootstrap(v_orb.in(), corbalocs://sling.com:2143);

// Resolve SecurityCurrent

CORBA::Object_ptr seccurobj = 
        bootstrap.resolve_initial_references("SecurityCurrent");
SecurityLevel2::Current_ptr seccur = 
        SecurityLevel2::Current::_narrow(seccurobj);

// Perform certificate-based authentication
        SecurityLevel2::Credentials_ptr						the_creds;
        Security::AttributeList_var					privileges;
        Security::Opaque_var continuation_data;
        Security::Opaque_var auth_specific_data;
        Security::Opaque_var response_data;

//Principal email address
        char emailAddress[] = "milozzi@bigcompany.com;"
// Pass phrase for principal's digital certificate
        char password[] = "asdawrewe98infldi7;"

// Convert the certificate private key password to opaque
        unsigned long password_len = strlen(password);
         Security::Opaque ssl_auth_data(password_len);

// Authenticate principal certificate with principal authenticator
          for(int i = 0; (unsigned long) i < password_len; i++)
          ssl_auth_data[i] = password[i];
          Security::AuthenticationStatus auth_status;
          SecurityLevel2::PrincipalAuthenticator_var PA = 
                           seccur->principal_authenticator();

          auth_status = PA->authenticate(Tobj::CertificateBased, 
                                         emailAddress, 
                                         ssl_auth_data,
                                         privileges, 
                                         the_creds, 
                                         continuation_data, 
                                          auth_specific_data);

		while(auth_status == Security::SecAuthContinue) {
		auth_status = PA->continue_authentication(
                                         response_data,
                                         the_creds,
                                         continuation_data,
                                          auth_specific_data);

		}

...

Using the Interoperable Naming Service Mechanism

To use the Interoperable Naming Service mechanism to access the BEA Tuxedo domain with the proper credentials, perform the following steps:

For more information about using the CORBA Interoperable Naming Service (INS) mechanism, see the CORBA Bootstrap Object Programming Reference for the SecurityLevel2::PrincipalAuthenticator interface.

Protecting the Client Credentials

The following information provides a sample that protects the client credentials before performing the step of continuing authentication.

The following example assumes a Java client using J2SE v 1.4, accessing a BEA Tuxedo application.

Using the Invocations_Options_Required() Method

When using certificate authentication, it may be necessary for a principal to explicitly define the security attributes it requires. For example, a bank application may have specific security requirements it needs to meet before the bank application can transfer data to a database. The invocation_options_required() method of the SecurityLevel2::Credentials interface allows the principal to explicitly control the security characteristics of the SSL connection. When using the corbaloc URL address format, you can secure the bootstrapping process by using the authenticate()and invocation_options_required() methods of the SecurityLevel2::Credentials interface.

To use the invocation_options_required() method, complete the following steps:

Listing 9-7 provides a C++ example that uses the invocation_options_required() method.

// Initialize the ORB
CORBA::ORB_var v_orb = CORBA::ORB_init(argc, argv, "");

// Create the bootstrap object
Tobj_Bootstrap bootstrap(v_orb.in(), corbalocs://sling.com:2143);

// Resolve SecurityCurrent

CORBA::Object_ptr seccurobj = 
        bootstrap.resolve_initial_references("SecurityCurrent");
SecurityLevel2::Current_ptr seccur = 
        SecurityLevel2::Current::_narrow(seccurobj);

// Perform certificate-based authentication
        SecurityLevel2::Credentials_ptr						the_creds;
Security::AttributeList_var					privileges;
        Security::Opaque_var continuation_data;
        Security::Opaque_var auth_specific_data;
        Security::Opaque_var response_data;

//Principal email address
        char emailAddress[] = "milozzi@bigcompany.com;"
// Pass phrase for principal's digital certificate
        char password[] = "asdawrewe98infldi7;"

// Convert the certificate private key password to opaque
        unsigned long password_len = strlen(password);
         Security::Opaque ssl_auth_data(password_len);

// Authenticate principal certificate with principal authenticator
          for(int i = 0; (unsigned long) i < password_len; i++)
          ssl_auth_data[i] = password[i];
          Security::AuthenticationStatus auth_status;
          SecurityLevel2::PrincipalAuthenticator_var PA = 
                           seccur->principal_authenticator();

          auth_status = PA->authenticate(Tobj::CertificateBased, 
                                         emailAddress, 
                                         ssl_auth_data,
                                         privileges, 
                                         the_creds, 
                                         continuation_data, 
                                          auth_specific_data);
          the_creds->invocation_options_required(
                               Security::Integrity|
                               Security::DetectReplay|
                               Security::DetectMisordering|
                               Security::EstablishTrustInTarget|
                               Security::EstalishTrustInClient|
				   Security::SimpleDelegation);

          while(auth_status == Security::SecAuthContinue) {
		  auth_status = PA->continue_authentication(
                                         response_data,
                                         the_creds,
                                         continuation_data,
                                          auth_specific_data);

		}