ndn_app/
lib.rs

1use bytes::{BufMut, Bytes, BytesMut};
2use error::Error;
3use log::warn;
4use ndn_ndnlp::{LpPacket, Packet};
5use ndn_protocol::{Data, Interest, Name};
6use ndn_tlv::{Tlv, TlvDecode, TlvEncode, VarNum};
7use tokio::io::{AsyncRead, AsyncReadExt};
8
9pub mod app;
10pub mod error;
11mod util;
12pub mod verifier;
13
14pub type Result<T> = std::result::Result<T, Error>;
15
16trait ToName {
17    fn to_name(self) -> Name;
18}
19
20impl ToName for &str {
21    fn to_name(self) -> Name {
22        Name::from_str(self).unwrap()
23    }
24}
25
26impl ToName for Name {
27    fn to_name(self) -> Name {
28        self
29    }
30}
31
32trait DataExt: Sized {
33    async fn from_async_reader(reader: impl AsyncRead + Unpin) -> Option<Self>;
34}
35
36impl DataExt for Packet {
37    async fn from_async_reader(mut reader: impl AsyncRead + Unpin) -> Option<Self> {
38        const BUFFER_SIZE: usize = 1024;
39
40        let mut header_buf = [0; 18];
41        let bytes_read = reader.read(&mut header_buf).await.ok()?;
42        let mut header_bytes = Bytes::copy_from_slice(&header_buf);
43
44        if bytes_read == 0 {
45            return None;
46        }
47
48        let typ = VarNum::decode(&mut header_bytes).ok()?;
49        let len = VarNum::decode(&mut header_bytes).ok()?;
50        if typ.value() as usize != Interest::<()>::TYP
51            && typ.value() as usize != Data::<()>::TYP
52            && typ.value() as usize != LpPacket::TYP
53        {
54            // Unknown TLV type, skip the rest and return
55            warn!("Unknown TLV type {typ} received");
56            let remaining_len = len.value() as usize - bytes_read;
57            tokio::io::copy(
58                &mut reader.take(remaining_len as u64),
59                &mut tokio::io::sink(),
60            )
61            .await
62            .expect("Failed to read unknown packet");
63            return None;
64        }
65
66        let total_len = typ.size() + len.size() + len.value() as usize;
67
68        let mut bytes = BytesMut::with_capacity(total_len);
69        bytes.put(&header_buf[0..bytes_read]);
70
71        let mut left_to_read = total_len - bytes_read;
72        let mut buf = [0; BUFFER_SIZE];
73        while left_to_read > 0 {
74            let bytes_read = reader
75                .read(&mut buf[0..left_to_read.min(BUFFER_SIZE)])
76                .await
77                .ok()?;
78            bytes.put(&buf[..left_to_read.min(BUFFER_SIZE)]);
79            left_to_read -= bytes_read;
80        }
81
82        Self::decode(&mut bytes.freeze()).ok()
83    }
84}
ndn_app/lib.rs

ndn_app/
lib.rs
