crypto/src/tls/TlsRsaUtilities.cs


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using System;
using System.IO;

using Org.BouncyCastle.Tls.Crypto;

namespace Org.BouncyCastle.Tls
{
    /// <summary>RSA utility methods.</summary>
    public abstract class TlsRsaUtilities
    {
        /// <summary>Generate a pre_master_secret and send it encrypted to the server.</summary>
        /// <exception cref="IOException"/>
        public static TlsSecret GenerateEncryptedPreMasterSecret(TlsContext context, TlsCertificate certificate,
            Stream output)
        {
            TlsSecret preMasterSecret = context.Crypto.GenerateRsaPreMasterSecret(context.RsaPreMasterSecretVersion);

            TlsEncryptor encryptor = certificate.CreateEncryptor(TlsCertificateRole.RsaEncryption);

            byte[] encryptedPreMasterSecret = preMasterSecret.Encrypt(encryptor);
            TlsUtilities.WriteEncryptedPms(context, encryptedPreMasterSecret, output);

            return preMasterSecret;
        }
    }
}