public STUNAttribute FindAttribute(StunAttributeType type)
{
foreach (STUNAttributeContainer cont in Attributes)
{
if (cont.ParsedAttribute.Type == type)
{
return(cont.ParsedAttribute);
}
}
return(null);
}
// Construct a message from a received byte array
public StunMessage(byte[] bytes)
{
// take a copy of the bytes as we can't assume that ownership is transferred
buffer = new byte[bytes.Length];
Array.Copy(bytes, buffer, bytes.Length);
// extract some often used fields
type = ExtractShort(buffer, 0);
length = ExtractShort(buffer, 2);
transactionID = new byte[12];
Array.Copy(bytes, 8, transactionID, 0, 12);
// scan through the rest of the buffer to build a list of available attributes
availableAttributes = new List <StunAttributeType>();
int pos = 20;
while (pos < buffer.Length)
{
StunAttributeType type = (StunAttributeType)ExtractShort(buffer, pos);
availableAttributes.Add(type);
pos += 2;
ushort length = ExtractShort(buffer, pos);
pos += 2;
// TODO: it might just be easier to get all the values too, especially the nonce which needs some special processing
// when getting the nonce, check for the cookie, base64 decode the next 4 bytes and deconstruct the bit field
if (type == StunAttributeType.NONCE)
{
byte[] value = new byte[length];
Array.Copy(buffer, pos, value, 0, length);
nonce = System.Text.Encoding.UTF8.GetString(value);
if (NonceMatchesCookie())
{
securityFeatureSet = Convert.FromBase64String(nonce.Substring(9, 4));
}
}
else if (type == StunAttributeType.ERROR_CODE)
{
ErrorCode = buffer[pos + 2] * 100 + buffer[pos + 3];
ErrorReason = System.Text.Encoding.UTF8.GetString(buffer, 4, length - 4);
}
pos += length;
}
}
/// <summary>
/// Constructs a new StunAttribute
/// </summary>
/// <param name="type">The type of this StunAttribute</param>
/// <param name="typeBytes">The value of the type of this StunAttribute in bytes</param>
/// <param name="value">The value of this StunAttribute</param>
public StunAttribute(StunAttributeType type, byte[] typeBytes, byte[] value)
{
if (typeBytes == null)
{
throw new ArgumentNullException("value", "Cannot be null");
}
if (value == null)
{
throw new ArgumentNullException("value", "Cannot be null");
}
switch (type)
{
case StunAttributeType.Software:
case StunAttributeType.Realm:
case StunAttributeType.Nonce:
case StunAttributeType.ErrorCode:
if (value.Length > 763)
{
throw new ArgumentOutOfRangeException("value", "Cannot be greater than 763 bytes for the given type as described in RFC 5389");
}
break;
case StunAttributeType.Username:
if (value.Length > 513)
{
throw new ArgumentOutOfRangeException("value", "Cannot be greater than 513 bytes for the given type as described in RFC 5389");
}
break;
}
switch (type)
{
case StunAttributeType.Realm:
case StunAttributeType.Username:
String saslPrepValue = new SASLprep().Prepare(StunMessage.Encoder.GetString(value));
value = StunMessage.Encoder.GetBytes(saslPrepValue);
break;
}
this.TypeBytes = typeBytes;
this.Type = type;
this.Value = value;
}
/// <summary>
/// Convert a StunAttributeType to a network-byte ordered array of bytes
/// </summary>
/// <param name="type">The StunAttributeType to convert</param>
/// <returns>
/// The array of 2 bytes (16bits) matching the StunAttributeType
/// Returns max UInt16 value if the type parameter is StunAttributeType.Unmanaged
/// </returns>
public static byte[] AttributeTypeToBytes(StunAttributeType type)
{
foreach (FieldInfo field in typeof(StunAttributeType).GetFields())
{
if (field.Name == type.ToString())
{
Object[] fieldAttributes = field.GetCustomAttributes(typeof(StunValueAttribute), false);
if (fieldAttributes.Length == 1)
{
StunValueAttribute stunValueAttribute = fieldAttributes.GetValue(0) as StunValueAttribute;
byte[] typeBytes = BitConverter.GetBytes(stunValueAttribute.Value);
Array.Reverse(typeBytes);
return(typeBytes);
}
}
}
return(BitConverter.GetBytes(0xFFFF));
}
/// <summary>
/// Constructs a new StunAttribute
/// </summary>
/// <param name="type">The type of this StunAttribute</param>
/// <param name="value">The value of this StunAttribute</param>
public StunAttribute(StunAttributeType type, byte[] value)
: this(type, StunAttribute.AttributeTypeToBytes(type), value)
{
}
/// <summary>
/// Constructs a XorMappedAddress based on an existing StunAttribute
/// </summary>
/// <param name="type">The StunAttributeType associated with the attribute parameter</param>
/// <param name="attribute">The StunAttribute base for this XorMappedAddress</param>
/// <param name="transactionID">
/// The transaction ID of the message from where the attribute parameter originates
/// It may be used by this XorMappedAddress to decode an IPV6 address
/// </param>
public XorMappedAddress(StunAttributeType type, StunAttribute attribute, byte[] transactionID)
: base(type, attribute)
{
this.TransactionID = transactionID;
}
/// <summary>
/// Constructs an empty MappedAddress
/// </summary>
/// <param name="type">The StunAttributeType of this MappedAddress</param>
protected MappedAddress(StunAttributeType type)
: base(type)
{ }
/// <summary>
/// Constructs a MappedAddress based on an existing StunAttribute
/// </summary>
/// <param name="type">The StunAttributeType associated with the attribute parameter</param>
/// <param name="attribute">The StunAttribute base for this MappedAddress</param>
public MappedAddress(StunAttributeType type, StunAttribute attribute)
: base(type, attribute.Value)
{ }
/// <summary>
/// Constructs an HexAttribute based on an existing StunAttribute
/// </summary>
/// <param name="attribute">The StunAttribute base for this HexAttribute</param>
public HexAttribute(StunAttributeType type, StunAttribute attribute)
: base(type, attribute.Value)
{ }
/// <summary>
/// Constructs an empty StunAttribute
/// </summary>
public StunAttribute(StunAttributeType type)
{ }
/// <summary>
/// Constructs a new UTF8Attribute
/// </summary>
/// <param name="type">The type of this UTF8Attribute</param>
/// <param name="value">The value of this UTF8Attribute</param>
public UTF8Attribute(StunAttributeType type, String value)
: base(type, StunMessage.Encoder.GetBytes(value))
{
}
/// <summary>
/// Constructs a new StunAttribute
/// </summary>
/// <param name="type">The type of this StunAttribute</param>
/// <param name="value">The value of this StunAttribute</param>
public StunAttribute(StunAttributeType type, byte[] value)
: this(type, StunAttribute.AttributeTypeToBytes(type), value)
{ }
public STUNAttribute FindAttribute(StunAttributeType type)
{
foreach (STUNAttributeContainer cont in Attributes)
{
if (cont.ParsedAttribute.Type == type)
{
return cont.ParsedAttribute;
}
}
return null;
}
public bool HasAttribute(StunAttributeType attribute)
{
return(availableAttributes.Contains(attribute));
}
/// <summary>
/// Constructs an empty StunAttribute
/// </summary>
public StunAttribute(StunAttributeType type)
{
}
/// <summary>
/// Constructs a XorMappedAddress based on an existing StunAttribute
/// </summary>
/// <param name="type">The StunAttributeType associated with the attribute parameter</param>
/// <param name="attribute">The StunAttribute base for this XorMappedAddress</param>
/// <param name="transactionID">
/// The transaction ID of the message from where the attribute parameter originates
/// It may be used by this XorMappedAddress to decode an IPV6 address
/// </param>
public XorMappedAddress(StunAttributeType type, StunAttribute attribute, byte[] transactionID)
: base(type, attribute)
{
this.TransactionID = transactionID;
}
/// <summary>
/// Constructs an empty MappedAddress
/// </summary>
/// <param name="type">The StunAttributeType of this MappedAddress</param>
protected MappedAddress(StunAttributeType type)
: base(type)
{
}
/// <summary>
/// Constructs a MappedAddress based on an existing StunAttribute
/// </summary>
/// <param name="type">The StunAttributeType associated with the attribute parameter</param>
/// <param name="attribute">The StunAttribute base for this MappedAddress</param>
public MappedAddress(StunAttributeType type, StunAttribute attribute)
: base(type, attribute.Value)
{
}
/// <summary>
/// Constructs a new StunAttribute
/// </summary>
/// <param name="type">The type of this StunAttribute</param>
/// <param name="typeBytes">The value of the type of this StunAttribute in bytes</param>
/// <param name="value">The value of this StunAttribute</param>
public StunAttribute(StunAttributeType type, byte[] typeBytes, byte[] value)
{
if (typeBytes == null)
throw new ArgumentNullException("value", "Cannot be null");
if (value == null)
throw new ArgumentNullException("value", "Cannot be null");
switch (type)
{
case StunAttributeType.Software:
case StunAttributeType.Realm:
case StunAttributeType.Nonce:
case StunAttributeType.ErrorCode:
if (value.Length > 763)
throw new ArgumentOutOfRangeException("value", "Cannot be greater than 763 bytes for the given type as described in RFC 5389");
break;
case StunAttributeType.Username:
if (value.Length > 513)
throw new ArgumentOutOfRangeException("value", "Cannot be greater than 513 bytes for the given type as described in RFC 5389");
break;
}
switch (type)
{
case StunAttributeType.Realm:
case StunAttributeType.Username:
String saslPrepValue = new SASLprep().Prepare(StunMessage.Encoder.GetString(value));
value = StunMessage.Encoder.GetBytes(saslPrepValue);
break;
}
this.TypeBytes = typeBytes;
this.Type = type;
this.Value = value;
}
void SetAttribute(STUNAttribute attr)
{
StunAttributeType = attr.Type;
m_objParsedAttribute = attr;
}
/// <summary>
/// Retrieve the attribute of a given type in this message
/// </summary>
/// <param name="type">The type of the attribute to retrieve</param>
/// <returns>The known attribute matching the given type or null if it doesn't exists</returns>
public StunAttribute GetAttribute(StunAttributeType type)
{
return this.attributesList.ContainsKey(type) ? this.attributesList[type] : null;
}
public STUNAttribute(StunAttributeType nType)
{
Type = nType;
}
/// <summary>
/// Retrieve the attribute of a given type in this message
/// </summary>
/// <param name="type">The type of the attribute to retrieve</param>
/// <returns>The known attribute matching the given type or null if it doesn't exists</returns>
public StunAttribute GetAttribute(StunAttributeType type)
{
return(this.attributesList.ContainsKey(type) ? this.attributesList[type] : null);
}
public STUNAttribute(StunAttributeType nType)
{
Type = nType;
}
/// <summary>
/// Constructs a new UTF8Attribute
/// </summary>
/// <param name="type">The type of this UTF8Attribute</param>
/// <param name="value">The value of this UTF8Attribute</param>
public UTF8Attribute(StunAttributeType type, String value)
: base(type, StunMessage.Encoder.GetBytes(value))
{ }
/// <summary>
/// Constructs an HexAttribute based on an existing StunAttribute
/// </summary>
/// <param name="attribute">The StunAttribute base for this HexAttribute</param>
public HexAttribute(StunAttributeType type, StunAttribute attribute)
: base(type, attribute.Value)
{
}
/// <summary>
/// Convert a StunAttributeType to a network-byte ordered array of bytes
/// </summary>
/// <param name="type">The StunAttributeType to convert</param>
/// <returns>
/// The array of 2 bytes (16bits) matching the StunAttributeType
/// Returns max UInt16 value if the type parameter is StunAttributeType.Unmanaged
/// </returns>
public static byte[] AttributeTypeToBytes(StunAttributeType type)
{
foreach (FieldInfo field in typeof(StunAttributeType).GetFields())
{
if (field.Name == type.ToString())
{
Object[] fieldAttributes = field.GetCustomAttributes(typeof(StunValueAttribute), false);
if (fieldAttributes.Length == 1)
{
StunValueAttribute stunValueAttribute = fieldAttributes.GetValue(0) as StunValueAttribute;
byte[] typeBytes = BitConverter.GetBytes(stunValueAttribute.Value);
Array.Reverse(typeBytes);
return typeBytes;
}
}
}
return BitConverter.GetBytes(0xFFFF);
}
