socks5_impl/protocol/
udp.rs

1#[cfg(feature = "tokio")]
2use crate::protocol::AsyncStreamOperation;
3use crate::protocol::{Address, StreamOperation};
4#[cfg(feature = "tokio")]
5use tokio::io::{AsyncRead, AsyncReadExt};
6
7/// SOCKS5 UDP packet header
8///
9/// ```plain
10/// +-----+------+------+----------+----------+----------+
11/// | RSV | FRAG | ATYP | DST.ADDR | DST.PORT |   DATA   |
12/// +-----+------+------+----------+----------+----------+
13/// |  2  |  1   |  1   | Variable |    2     | Variable |
14/// +-----+------+------+----------+----------+----------+
15/// ```
16#[derive(Clone, Debug)]
17pub struct UdpHeader {
18    pub frag: u8,
19    pub address: Address,
20}
21
22impl UdpHeader {
23    pub fn new(frag: u8, address: Address) -> Self {
24        Self { frag, address }
25    }
26
27    pub const fn max_serialized_len() -> usize {
28        3 + Address::max_serialized_len()
29    }
30}
31
32impl StreamOperation for UdpHeader {
33    fn retrieve_from_stream<R: std::io::Read>(stream: &mut R) -> std::io::Result<Self> {
34        let mut buf = [0; 3];
35        stream.read_exact(&mut buf)?;
36
37        if buf[0] != 0x00 || buf[1] != 0x00 {
38            return Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "invalid UDP reserved bytes"));
39        }
40
41        let frag = buf[2];
42
43        let address = Address::retrieve_from_stream(stream)?;
44        Ok(Self { frag, address })
45    }
46
47    fn write_to_buf<B: bytes::BufMut>(&self, buf: &mut B) {
48        buf.put_bytes(0x00, 2);
49        buf.put_u8(self.frag);
50        self.address.write_to_buf(buf);
51    }
52
53    fn len(&self) -> usize {
54        3 + self.address.len()
55    }
56}
57
58#[cfg(feature = "tokio")]
59#[async_trait::async_trait]
60impl AsyncStreamOperation for UdpHeader {
61    async fn retrieve_from_async_stream<R>(r: &mut R) -> std::io::Result<Self>
62    where
63        R: AsyncRead + Unpin + Send + ?Sized,
64    {
65        let mut buf = [0; 3];
66        r.read_exact(&mut buf).await?;
67
68        if buf[0] != 0x00 || buf[1] != 0x00 {
69            return Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "invalid UDP reserved bytes"));
70        }
71
72        let frag = buf[2];
73
74        let address = Address::retrieve_from_async_stream(r).await?;
75        Ok(Self { frag, address })
76    }
77}
socks5_impl/protocol/udp.rs

socks5_impl/protocol/
udp.rs
