Getting error while sending push notification to ios from c#

int port = 2195;

string hostname = "gateway.sandbox.push.apple.com";

// String hostname = "gateway.push.apple.com";

String certificatePath = Server.MapPath("PushnotificationDev.p12");

X509Certificate2 clientCertificate = new X509Certificate2(System.IO.File.ReadAllBytes(certificatePath), "password");

X509Certificate2Collection certificatesCollection = new X509Certificate2Collection(clientCertificate);

TcpClient client = new TcpClient(hostname, port);

SslStream sslStream = new SslStream(client.GetStream(), false, new RemoteCertificateValidationCallback(ValidateServerCertificate), null);

try

{

// client.Connect(hostname,port);

//sslStream.AuthenticateAsServer(hostname, certificatesCollection, SslProtocols.Default, true);

ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3;

sslStream.AuthenticateAsServer(clientCertificate, false, SslProtocols.Ssl3, true);

MemoryStream memoryStream = new MemoryStream();

BinaryWriter writer = new BinaryWriter(memoryStream);

writer.Write((byte)0);

writer.Write((byte)0);

writer.Write((byte)32);

writer.Write(ConvertToByteArray("0755ac6c555e9b9e819b15772e6bcb11d64c659d331a28cf7674050a20fa846e"));

String payload = "{\"aps\":{\"alert\":\"" + "Hi,, This Is a Sample Push Notification For IPhone.." + "\",\"badge\":1,\"sound\":\"default\"}}";

writer.Write((byte)0);

writer.Write((byte)payload.Length);

byte[] b1 = System.Text.Encoding.UTF8.GetBytes(payload);

writer.Write(b1);

writer.Flush();

byte[] array = memoryStream.ToArray();

sslStream.Write(array);

sslStream.Flush();

client.Close();

}

catch (System.Security.Authentication.AuthenticationException ex)

{

client.Close();

}

catch (Exception ex)

{

lblenc.Text = ex.Message;

client.Close();

}

}

public static byte[] ConvertToByteArray(string value)

{

byte[] bytes = null;

if (String.IsNullOrEmpty(value))

bytes = null;

else

{

int string_length = value.Length;

int character_index = (value.StartsWith("0x", StringComparison.Ordinal)) ? 2 : 0; // Does the string define leading HEX indicator '0x'. Adjust starting index accordingly.

int number_of_characters = string_length - character_index;

bool add_leading_zero = false;

if (0 != (number_of_characters % 2))

{

add_leading_zero = true;

number_of_characters += 1; // Leading '0' has been striped from the string presentation.

}

bytes = new byte[number_of_characters / 2]; // Initialize our byte array to hold the converted string.

int write_index = 0;

if (add_leading_zero)

{

bytes[write_index++] = FromCharacterToByte(value[character_index], character_index);

character_index += 1;

}

for (int read_index = character_index; read_index < value.Length; read_index += 2)

{

byte upper = FromCharacterToByte(value[read_index], read_index, 4);

byte lower = FromCharacterToByte(value[read_index + 1], read_index + 1);

bytes[write_index++] = (byte)(upper | lower);

}

}

return bytes;

}

private static byte FromCharacterToByte(char character, int index, int shift = 0)

{

byte value = (byte)character;

if (((0x40 < value) && (0x47 > value)) || ((0x60 < value) && (0x67 > value)))

{

if (0x40 == (0x40 & value))

{

if (0x20 == (0x20 & value))

value = (byte)(((value + 0xA) - 0x61) << shift);

else

value = (byte)(((value + 0xA) - 0x41) << shift);

}

}

else if ((0x29 < value) && (0x40 > value))

value = (byte)((value - 0x30) << shift);

else

throw new InvalidOperationException(String.Format("Character '{0}' at index '{1}' is not valid alphanumeric character.", character, index));

return value;

}

public static bool ValidateServerCertificate(

object sender,

X509Certificate certificate,

X509Chain chain,

SslPolicyErrors sslPolicyErrors)

{

if (sslPolicyErrors == SslPolicyErrors.None)

return true;

Console.WriteLine("Certificate error: {0}", sslPolicyErrors);

// Do not allow this client to communicate with unauthenticated servers.

return false;

}

private byte[] HexString2Bytes(String hexString)

{

//check for null

if (hexString == null) return null;

//get length

int len = hexString.Length;

if (len % 2 == 1) return null;

int len_half = len / 2;

//create a byte array

byte[] bs = new byte[len_half];

try

{

//convert the hexstring to bytes

for (int i = 0; i != len_half; i++)

{

bs[i] = (byte)Int32.Parse(hexString.Substring(i * 2, 2), System.Globalization.NumberStyles.HexNumber);

}

}

catch (Exception ex)

{

//MessageBox.Show("Exception : " + ex.Message);

}

//return the byte array

return bs;

}