vpncloud/src/messages.rs

266 lines
9.4 KiB
Rust

// VpnCloud - Peer-to-Peer VPN
// Copyright (C) 2015-2021 Dennis Schwerdel
// This software is licensed under GPL-3 or newer (see LICENSE.md)
use crate::{
crypto::Payload,
error::Error,
types::{NodeId, Range, RangeList, NODE_ID_BYTES},
util::MsgBuffer,
};
use byteorder::{NetworkEndian, ReadBytesExt, WriteBytesExt};
use smallvec::{smallvec, SmallVec};
use std::{
io::{self, Cursor, Read, Seek, SeekFrom, Take, Write},
net::{Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV4, SocketAddrV6},
};
pub const MESSAGE_TYPE_DATA: u8 = 0;
pub const MESSAGE_TYPE_NODE_INFO: u8 = 1;
pub const MESSAGE_TYPE_KEEPALIVE: u8 = 2;
pub const MESSAGE_TYPE_CLOSE: u8 = 0xff;
pub type AddrList = SmallVec<[SocketAddr; 4]>;
pub type PeerList = SmallVec<[PeerInfo; 16]>;
#[derive(Debug, PartialEq)]
pub struct PeerInfo {
pub node_id: Option<NodeId>,
pub addrs: AddrList,
}
#[derive(Debug, PartialEq)]
pub struct NodeInfo {
pub node_id: NodeId,
pub peers: PeerList,
pub claims: RangeList,
pub peer_timeout: Option<u16>,
pub addrs: AddrList,
}
impl NodeInfo {
const PART_CLAIMS: u8 = 2;
const PART_END: u8 = 0;
const PART_NODEID: u8 = 4;
const PART_PEERS: u8 = 1;
const PART_PEER_TIMEOUT: u8 = 3;
const PART_ADDRS: u8 = 5;
fn read_addr_list<R: Read>(r: &mut Take<R>) -> Result<AddrList, io::Error> {
let flags = r.read_u8()?;
Self::read_addr_list_inner(r, flags)
}
fn read_addr_list_inner<R: Read>(r: &mut Take<R>, flags: u8) -> Result<AddrList, io::Error> {
let num_ipv4_addrs = (flags & 0x07) as usize;
let num_ipv6_addrs = (flags & 0x38) as usize / 8;
let mut addrs = SmallVec::with_capacity(num_ipv4_addrs + num_ipv6_addrs);
for _ in 0..num_ipv6_addrs {
let mut ip = [0u8; 16];
r.read_exact(&mut ip)?;
let port = r.read_u16::<NetworkEndian>()?;
let addr = SocketAddr::V6(SocketAddrV6::new(Ipv6Addr::from(ip), port, 0, 0));
addrs.push(addr);
}
for _ in 0..num_ipv4_addrs {
let mut ip = [0u8; 4];
r.read_exact(&mut ip)?;
let port = r.read_u16::<NetworkEndian>()?;
let addr = SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::from(ip), port));
addrs.push(addr);
}
Ok(addrs)
}
fn decode_peer_list_part<R: Read>(r: &mut Take<R>) -> Result<PeerList, io::Error> {
let mut peers = smallvec![];
while r.limit() > 0 {
let flags = r.read_u8()?;
let has_node_id = (flags & 0x80) != 0;
let mut node_id = None;
if has_node_id {
let mut id = [0; NODE_ID_BYTES];
r.read_exact(&mut id)?;
node_id = Some(id)
}
let addrs = Self::read_addr_list_inner(r, flags)?;
peers.push(PeerInfo { addrs, node_id })
}
Ok(peers)
}
fn decode_claims_part<R: Read>(mut r: &mut Take<R>) -> Result<RangeList, Error> {
let mut claims = smallvec![];
while r.limit() > 0 {
claims.push(Range::read_from(&mut r)?);
}
Ok(claims)
}
fn decode_internal<R: Read>(mut r: R) -> Result<Self, Error> {
let mut peers = smallvec![];
let mut claims = smallvec![];
let mut peer_timeout = None;
let mut node_id = None;
let mut addrs = smallvec![];
loop {
let part = r.read_u8().map_err(|_| Error::Message("Truncated message"))?;
if part == Self::PART_END {
break;
}
let part_len = r.read_u16::<NetworkEndian>().map_err(|_| Error::Message("Truncated message"))? as usize;
let mut rp = r.take(part_len as u64);
match part {
Self::PART_PEERS => {
peers = Self::decode_peer_list_part(&mut rp).map_err(|_| Error::Message("Truncated message"))?
}
Self::PART_CLAIMS => claims = Self::decode_claims_part(&mut rp)?,
Self::PART_PEER_TIMEOUT => {
peer_timeout =
Some(rp.read_u16::<NetworkEndian>().map_err(|_| Error::Message("Truncated message"))?)
}
Self::PART_NODEID => {
let mut data = [0; NODE_ID_BYTES];
rp.read_exact(&mut data).map_err(|_| Error::Message("Truncated message"))?;
node_id = Some(data);
}
Self::PART_ADDRS => {
addrs = Self::read_addr_list(&mut rp).map_err(|_| Error::Message("Truncated message"))?;
}
_ => {
let mut data = vec![0; part_len];
rp.read_exact(&mut data).map_err(|_| Error::Message("Truncated message"))?;
}
}
r = rp.into_inner();
}
let node_id = match node_id {
Some(node_id) => node_id,
None => return Err(Error::Message("Payload without node_id")),
};
Ok(Self { node_id, peers, claims, peer_timeout, addrs })
}
pub fn decode<R: Read>(r: R) -> Result<Self, Error> {
Self::decode_internal(r).map_err(|_| Error::Message("Input data too short"))
}
fn encode_peer_list_part<W: Write>(&self, mut out: W) -> Result<(), io::Error> {
for p in &self.peers {
let mut addr_ipv4: SmallVec<[SocketAddrV4; 16]> = smallvec![];
let mut addr_ipv6: SmallVec<[SocketAddrV6; 16]> = smallvec![];
for a in &p.addrs {
match a {
SocketAddr::V4(addr) => addr_ipv4.push(*addr),
SocketAddr::V6(addr) => addr_ipv6.push(*addr),
}
}
while addr_ipv4.len() >= 8 {
addr_ipv4.pop();
}
while addr_ipv6.len() >= 8 {
addr_ipv6.pop();
}
let mut flags = addr_ipv6.len() as u8 * 8 + addr_ipv4.len() as u8;
if p.node_id.is_some() {
flags += 0x80;
}
out.write_u8(flags)?;
if let Some(node_id) = &p.node_id {
out.write_all(node_id)?;
}
for a in addr_ipv6 {
out.write_all(&a.ip().octets())?;
out.write_u16::<NetworkEndian>(a.port())?;
}
for a in addr_ipv4 {
out.write_all(&a.ip().octets())?;
out.write_u16::<NetworkEndian>(a.port())?;
}
}
Ok(())
}
fn encode_addrs_part<W: Write>(&self, mut out: W) -> Result<(), io::Error> {
let mut addr_ipv4: SmallVec<[SocketAddrV4; 16]> = smallvec![];
let mut addr_ipv6: SmallVec<[SocketAddrV6; 16]> = smallvec![];
for a in &self.addrs {
match a {
SocketAddr::V4(addr) => addr_ipv4.push(*addr),
SocketAddr::V6(addr) => addr_ipv6.push(*addr),
}
}
while addr_ipv4.len() >= 8 {
addr_ipv4.pop();
}
while addr_ipv6.len() >= 8 {
addr_ipv6.pop();
}
let flags = addr_ipv6.len() as u8 * 8 + addr_ipv4.len() as u8;
out.write_u8(flags)?;
for a in addr_ipv6 {
out.write_all(&a.ip().octets())?;
out.write_u16::<NetworkEndian>(a.port())?;
}
for a in addr_ipv4 {
out.write_all(&a.ip().octets())?;
out.write_u16::<NetworkEndian>(a.port())?;
}
Ok(())
}
fn encode_part<F: FnOnce(&mut Cursor<&mut [u8]>) -> Result<(), io::Error>>(
cursor: &mut Cursor<&mut [u8]>, part: u8, f: F,
) -> Result<(), io::Error> {
cursor.write_u8(part)?;
cursor.write_u16::<NetworkEndian>(0)?;
let part_start = cursor.position();
f(cursor)?;
let part_end = cursor.position();
let len = part_end - part_start;
cursor.seek(SeekFrom::Start(part_start - 2))?;
cursor.write_u16::<NetworkEndian>(len as u16)?;
cursor.seek(SeekFrom::Start(part_end))?;
Ok(())
}
fn encode_internal(&self, buffer: &mut MsgBuffer) -> Result<(), io::Error> {
let len;
{
let mut cursor = Cursor::new(buffer.buffer());
Self::encode_part(&mut cursor, Self::PART_NODEID, |cursor| cursor.write_all(&self.node_id))?;
Self::encode_part(&mut cursor, Self::PART_PEERS, |cursor| self.encode_peer_list_part(cursor))?;
Self::encode_part(&mut cursor, Self::PART_CLAIMS, |mut cursor| {
for c in &self.claims {
c.write_to(&mut cursor);
}
Ok(())
})?;
if let Some(timeout) = self.peer_timeout {
Self::encode_part(&mut cursor, Self::PART_PEER_TIMEOUT, |cursor| {
cursor.write_u16::<NetworkEndian>(timeout)
})?
}
Self::encode_part(&mut cursor, Self::PART_ADDRS, |cursor| self.encode_addrs_part(cursor))?;
cursor.write_u8(Self::PART_END)?;
len = cursor.position() as usize;
}
buffer.set_length(len);
Ok(())
}
pub fn encode(&self, buffer: &mut MsgBuffer) {
self.encode_internal(buffer).expect("Buffer too small")
}
}
impl Payload for NodeInfo {
fn write_to(&self, buffer: &mut MsgBuffer) {
self.encode(buffer)
}
fn read_from<R: Read>(r: R) -> Result<Self, Error> {
Self::decode(r)
}
}