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pub struct Tcp<'p> {
src: u16,
dst: u16,
payload: &'p [u8],
}
impl<'p> Tcp<'p> {
pub fn new(buffer: &'p [u8]) -> Self {
let src = u16::from_be_bytes([buffer[0], buffer[1]]);
let dst = u16::from_be_bytes([buffer[2], buffer[3]]);
let data_offset = (buffer[12].to_be() & 0b1111_0000) >> 4;
// Offset is number of 32-bit words
let true_offset = data_offset as usize * 4;
Self {
src,
dst,
payload: &buffer[true_offset..],
}
}
pub fn source_port(&self) -> u16 {
self.src
}
pub fn destination_port(&self) -> u16 {
self.dst
}
pub fn payload(&self) -> &[u8] {
self.payload
}
}
pub struct Udp<'p> {
src: u16,
dst: u16,
payload: &'p [u8],
}
impl<'p> Udp<'p> {
pub fn new(buffer: &'p [u8]) -> Self {
let src = u16::from_be_bytes([buffer[0], buffer[1]]);
let dst = u16::from_be_bytes([buffer[2], buffer[3]]);
let _len = u16::from_be_bytes([buffer[4], buffer[5]]);
Self {
src,
dst,
payload: &buffer[8..],
}
}
pub fn source_port(&self) -> u16 {
self.src
}
pub fn destination_port(&self) -> u16 {
self.dst
}
pub fn payload(&self) -> &[u8] {
self.payload
}
}
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