#[error("Invalid SLIP escape sequence")] SLIP,
#[error("unexpected src addr {0:?}")] Src(IpAddr),
#[error("unexpected dst addr {0:?}")] Dst(IpAddr),
- #[error("bad, IPv{vsn}, len={len}")] Bad { len: usize, vsn: u8 },
+ #[error("truncated, IPv{vsn}, len={len}")] Truncated { len: usize, vsn: u8 },
}
pub trait SlipMime { const CONV_TO: Option<bool>; }
impl SlipMime for Mime2Slip { const CONV_TO: Option<bool> = Some(false); }
impl SlipMime for SlipNoConv { const CONV_TO: Option<bool> = None; }
-pub fn checkn<AC, EH, OUT, M: SlipMime+Copy>(
+#[derive(Debug,Error)]
+pub enum SlipFramesError<E> where E: std::error::Error + 'static {
+ #[error("only bad IP datagrams")] ErrorOnlyBad,
+ #[error("{0}")] Other(#[from] E),
+}
+
+#[throws(SlipFramesError<EHE>)]
+pub async fn checkn<AC, EH, EHE, OUT, FOUT, ACR, M: SlipMime+Copy>(
mime: M,
mtu: u32,
data: &[u8],
- out: &mut OUT,
addr_chk: AC,
+ mut out: OUT,
mut error_handler: EH
-) where OUT: Extend<Box<[u8]>>,
- AC: Fn(&[u8]) -> Result<(), PacketError> + Copy,
- EH: FnMut(PacketError),
+) where AC: Fn(&[u8]) -> Result<ACR, PacketError> + Copy + Send,
+ OUT: FnMut((Box<[u8]>, ACR)) -> FOUT + Send,
+ FOUT: Future<Output=Result<(), PacketError>> + Send,
+ EH: FnMut(PacketError) -> Result<(), SlipFramesError<EHE>> + Send,
+ EHE: std::error::Error + Send + 'static,
{
// eprintln!("before: {:?}", DumpHex(data));
if data.is_empty() { return }
+ let mut ok = false;
+ let mut err = false;
for packet in data.split(|&c| c == SLIP_END) {
- match check1(mime, mtu, packet, addr_chk) {
- Err(e) => error_handler(e),
- Ok(packet) => out.extend(iter::once(packet)),
+ match async {
+ let checked = check1(mime, mtu, packet, addr_chk);
+ if matches!(checked, Err(PacketError::Empty)) { return Ok::<_,PE>(()) }
+ out(checked?).await?;
+ ok = true;
+ Ok::<_,PE>(())
+ }.await {
+ Ok(()) => { },
+ Err(e) => { err=true; error_handler(e)?; },
}
}
// eprintln!(" after: {:?}", DumpHex(data));
+ if err && !ok { throw!(SlipFramesError::ErrorOnlyBad) }
}
#[throws(PacketError)]
-pub fn check1<AC, M: SlipMime>(
+pub fn check1<AC, M: SlipMime, ACR>(
_mime: M,
mtu: u32,
packet: &[u8],
addr_chk: AC,
-) -> Box<[u8]>
-where AC: Fn(&[u8]) -> Result<(), PacketError>,
+) -> (Box<[u8]>, ACR)
+where AC: Fn(&[u8]) -> Result<ACR, PacketError>,
{
if packet.len() == 0 {
throw!(PacketError::Empty)
}
- if packet.len() > mtu.sat() {
- throw!(PacketError::MTU { len: packet.len(), mtu });
- }
let mut packet: Box<[u8]> = packet.to_owned().into();
let mut walk: &mut [u8] = &mut packet;
let mut header = [0u8; HEADER_FOR_ADDR];
let mut wheader = &mut header[..];
+ let mut escapes = 0;
while let Some((i, was_mime)) = walk.iter().enumerate().find_map(
|(i,&c)| match c {
};
let _ = wheader.write(&[c]);
walk = &mut walk[i+2 ..];
+ escapes += 1;
} else {
let _ = wheader.write(&[SLIP_MIME_ESC]);
walk = &mut walk[i+1 ..];
let wheader_len = wheader.len();
let header = &header[0.. header.len() - wheader_len];
- addr_chk(&header)?;
+ let decoded_len = packet.len() - escapes;
+ if decoded_len > mtu.sat() {
+ throw!(PacketError::MTU { len: decoded_len, mtu });
+ }
- packet
+ let acr = addr_chk(&header)?;
+
+ (packet, acr)
}
pub type Frame = Vec<u8>;
const HEADER_FOR_ADDR: usize = 40;
#[throws(PacketError)]
-pub fn ip_packet_addr<const DST: bool>(packet: &[u8]) -> IpAddr {
- let vsn = (packet.get(0).ok_or_else(|| PE::Empty)? & 0xf0) >> 4;
+pub fn ip_packet_addr<const DST: bool>(header: &[u8]) -> IpAddr {
+ let vsn = (header.get(0).ok_or_else(|| PE::Empty)? & 0xf0) >> 4;
match vsn {
- 4 if packet.len() >= 20 => {
- let slice = &packet[if DST { 16 } else { 12 }..][0..4];
+ 4 if header.len() >= 20 => {
+ let slice = &header[if DST { 16 } else { 12 }..][0..4];
Ipv4Addr::from(*<&[u8;4]>::try_from(slice).unwrap()).into()
},
- 6 if packet.len() >= 40 => {
- let slice = &packet[if DST { 24 } else { 8 }..][0..16];
+ 6 if header.len() >= 40 => {
+ let slice = &header[if DST { 24 } else { 8 }..][0..16];
Ipv6Addr::from(*<&[u8;16]>::try_from(slice).unwrap()).into()
},
- _ => throw!(PE::Bad{ vsn, len: packet.len() }),
+ _ => throw!(PE::Truncated{ vsn, len: header.len() }),
}
}
#[throws(fmt::Error)]
fn fmt(&self, f: &mut fmt::Formatter) {
for v in self.0 { write!(f, "{:02x}", v)?; }
+ match str::from_utf8(self.0) {
+ Ok(s) => write!(f, "={:?}", s)?,
+ Err(x) => write!(f, "={:?}..",
+ str::from_utf8(&self.0[0..x.valid_up_to()]).unwrap()
+ )?,
+ }
}
}