Code Access Security

3.2 Code Access Security

ODP.NET implements code access security through the OraclePermission class. This ensures that application code trying to access the database has the requisite permission to do so.

When a .NET assembly tries to access Oracle Database through ODP.NET, ODP.NET demands OraclePermission. The .NET runtime security system checks to see whether the calling assembly, and all other assemblies in the call stack, have OraclePermission granted to them. If all assemblies in the call stack have OraclePermission granted to them, then the calling assembly can access the database. If any one of the assemblies in the call stack does not have OraclePermission granted to it, then a security exception is thrown.

3.2.1 Configuring OraclePermission

The DemandOraclePermission configuration attribute is used to enable or disable OraclePermission demand for an ODP.NET API. The DemandOraclePermission value can be specified in the Windows registry for unmanaged ODP.NET only, or an individual application configuration file for both unmanaged and managed ODP.NET.

The following Windows registry key is used to configure the DemandOraclePermission configuration attribute:

HKEY_LOCAL_MACHINE\SOFTWARE\ORACLE\ODP.NET\Assembly_Version\DemandOraclePermission

Here Assembly_Version is the full assembly version number of Oracle.DataAccess.dll. The DemandOraclePermission key is of type REG_SZ. It can be set to either 1 (enabled) or 0 (disabled).

You can also enable OraclePermission demand for an individual application using its application configuration file. The following example enables the DemandOraclePermission property in an application configuration file for ODP.NET, Unmanaged Driver:

<configuration>
  <oracle.dataaccess.client>
    <settings>
      <add name="DemandOraclePermission" value="1"/>
    </settings>
  </oracle.dataaccess.client>
</configuration>

Similarly, you can use DemandOraclePermission to configure ODP.NET, Managed Driver under the settings section for managed provider configuration. See also "settings section" for more information.

An application or assembly can successfully access the database if OraclePermission has been added to the permission set associated with the assembly's code group. A system administrator can modify the appropriate permission set manually or by using the Microsoft .NET configuration tool (Mscorcfg.msc).

Administrators may also use an appropriate .NET Framework Tool, such as the Code Access Security Policy Tool (Caspol.exe), to modify security policy at the machine, user, and enterprise levels for including OraclePermission.

OracleConnection makes security demands using the OraclePermission object when OraclePermission demand has been enabled using DemandOraclePermission configuration attribute. Application developers should make sure that their code has sufficient permission before using OracleConnection.

3.2.2 Configuring OraclePermission for Web Applications with High or Medium Trust Levels

For Web applications operating under high or medium trust, OraclePermission needs to be configured in the appropriate web_TrustLevel.config file, so that the application does not encounter any security errors.

OraclePermission can be configured using the OracProvCfg tool. OraProvCfg.exe adds appropriate entries to the web_hightrust.config and web_mediumtrust.config files associated with the specified .NET framework version.The following example illustrates using the OraProvCfg tool for configuring OraclePermission in a .NET 2.0 Web application:

OraProvCfg.exe /action:config  /product:odp /component:oraclepermission
               /frameworkversion:v2.0.50727
               /providerpath:full_path_of_Oracle.DataAccess.dll

On running the preceding command, the following entry is added to the web_hightrust.config and web_mediumtrust.config files under the ASP.NET permission set:

<IPermission class="Oracle.DataAccess.Client.OraclePermission, Oracle.DataAccess,
Version=2.112.2.0, Culture=neutral, PublicKeyToken=89b483f429c47342" version="1"
Unrestricted="true" />

OraProvCfg can also be used to remove these entries from the .config files when required. The following example illustrates this:

OraProvCfg.exe /action:unconfig  /product:odp  /component:oraclepermission
               /frameworkversion:v2.0.50727
               /providerpath:full_path_of_Oracle.DataAccess.dll

3.2.3 Configuring OraclePermission for Windows Applications Running in a Partial Trust Environment

For Windows applications operating in a partial trust environment, the OraclePermission entry should be specified under the appropriate permission set in the security.config file. The security.config file is available in the %windir%\Microsoft.NET\Framework\{version}\CONFIG folder.

The following example specifies the OraclePermission entry for a .NET 2.0 Windows application:

<IPermission class="Oracle.DataAccess.Client.OraclePermission, Oracle.DataAccess,
 Version=2.112.2.0, Culture=neutral, PublicKeyToken=89b483f429c47342" version="1"
 Unrestricted="true" />