Can I encrypt a string with RSA encryption using DBMS_CRYPTO?

Question

We have an web application that does a redirect thru a database package to a 3rd party site. They would like us to encrypt the querystring that is passed using RSA encryption. The example that they've given us (below) uses the RSA cryptographic service available in .NET. Is it possible to do this using DBMS_CRYPTO or some other method in Oracle?
Below are the steps outlined to use the key to generate the encrypted URL
2.1 Initialize Service
The RSA cryptographic service must be initialized with the provided public key. Below is sample code that can be used to initialize the service using the public key
C#
private void InitializeRSA( string keyFileName )
CspParameters cspParams = new CspParameters( );
cspParams.Flags = CspProviderFlags.UseMachineKeyStore;
m_sp = new RSACryptoServiceProvider( cspParams );
//Load the public key from the supplied XML file
StreamReader reader = new StreamReader( keyFileName );
string data = reader.ReadToEnd( );
//Initializes the public key
m_sp.FromXmlString( data );
2.2 Encryption method
Create a method that will encrypt a string using the cryptographic service that was initialized in step 2.1. The encryption method should convert the encryption method to Base64 to avoid special characters from being passed in the URL. Below is sample code that uses the method created in step 2.1 that can be used to encrypt a string.
C#
private string RSAEncrypt( string plainText )
ASCIIEncoding enc = new ASCIIEncoding( );
int numOfChars = enc.GetByteCount( plainText );
byte[ ] tempArray = enc.GetBytes( plainText );
byte[ ] result = m_sp.Encrypt( tempArray, false );
//Use Base64 encoding since the encrypted string will be used in an URL
return Convert.ToBase64String( result );
2.3 Generate URL
The query string must contain the necessary data elements configured for you school in Step 1. This will always include the Client Number and the Student ID of the student clicking on the link.
1.     Build the query string with Client Number and Student ID
C#
string queryString = “schoolId=1234&studentId=1234”;
The StudentCenter website will validate that the query string was generated within 3 minutes of the request being received on our server. A time stamp in UTC universal time (to prevent time zone inconsistencies) will need to be attached to the query string.
2.     Get the current UTC timestamp, and add the timestamp to the query string
C#
string dateTime = DateTime.UtcNow.ToString(“yyyy-MM-dd HH:mm:ss”);
queryString += “&currentDT=” + dateTime;
Now that the query string has all of the necessary parameters, use the RSAEncrypt (Step 2.2) method created early to encrypt the string. The encrypted string must also be url encoded to escape any special characters.
3.     Encrypt and Url Encode the query string
C#
string rsa = RSAEncrypt(querystring);
string eqs = Server.UrlEncode(rsa);
The encrypted query string is now appended to the Url (https://studentcenter.uhcsr.com), and is now ready for navigation.
4.     Build the URL
C#
string url = “https://studentcenter.uhcsr.com/custom.aspx?eqs=” + eqs

Answer 1

The documentation lists all the encyrption types:
http://download.oracle.com/docs/cd/B19306_01/appdev.102/b14258/d_crypto.htm#ARPLS664