Struct MessageHeader 

pub struct MessageHeader { /* private fields */ }

The fixed length header of a STUN message.

Allows reading the message header for a quick check if this message is a valid STUN message. Can also be used to expose the length of the complete message without needing to receive the entire message.

Implementations

impl MessageHeader

pub const LENGTH: usize = 20

The length of the STUN message header.

pub fn from_bytes(data: &[u8]) -> Result<Self, StunParseError>

Deserialize a MessageHeader.

If less than MessageHeader::LENGTH bytes are provided, the bytes that are available are still validated. StunParseError::NotStun is returned as soon as the data cannot be the start of a STUN message, and StunParseError::Truncated is only returned when the data may be the start of a STUN message. This allows a STUN message that is received in multiple pieces (e.g. over TCP) to be rejected as early as possible.

Examples

let msg_data = [0, 1, 0, 8, 33, 18, 164, 66, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 232];
let message = MessageHeader::from_bytes(&msg_data).unwrap();
assert_eq!(message.get_type(), MessageType::from_class_method(MessageClass::Request, BINDING));
assert_eq!(message.transaction_id(), 1000.into());
assert_eq!(message.data_length(), 8);

// The start of a STUN message header.
assert!(matches!(
    MessageHeader::from_bytes(&msg_data[..6]),
    Err(StunParseError::Truncated { expected: 20, actual: 6 })
));
// Not the start of a STUN message header, the magic cookie does not match.
assert!(matches!(
    MessageHeader::from_bytes(&[0, 1, 0, 8, 33, 0]),
    Err(StunParseError::NotStun)
));

pub fn data_length(&self) -> u16

The number of bytes of content in this MessageHeader. Adding both data_length() and MessageHeader::LENGTH will result in the size of the complete STUN message.

pub fn transaction_id(&self) -> TransactionId

The TransactionId of this MessageHeader.

pub fn get_type(&self) -> MessageType

The MessageType of this MessageHeader.

Trait Implementations

impl Debug for MessageHeader

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.