Zebra/zebra-chain/src/serialization/read_zcash.rs

99 lines
3.1 KiB
Rust

use std::{
io,
net::{IpAddr, Ipv6Addr, SocketAddr},
};
use byteorder::{BigEndian, ReadBytesExt};
/// Extends [`Read`] with methods for writing Zcash/Bitcoin types.
///
/// [`Read`]: https://doc.rust-lang.org/std/io/trait.Read.html
pub trait ReadZcashExt: io::Read {
/// Read an IP address in Bitcoin format.
#[inline]
fn read_ip_addr(&mut self) -> io::Result<IpAddr> {
let mut octets = [0u8; 16];
self.read_exact(&mut octets)?;
let v6_addr = Ipv6Addr::from(octets);
Ok(canonical_ip_addr(&v6_addr))
}
/// Read a Bitcoin-encoded `SocketAddr`.
#[inline]
fn read_socket_addr(&mut self) -> io::Result<SocketAddr> {
let ip_addr = self.read_ip_addr()?;
let port = self.read_u16::<BigEndian>()?;
Ok(SocketAddr::new(ip_addr, port))
}
/// Convenience method to read a `[u8; 4]`.
#[inline]
fn read_4_bytes(&mut self) -> io::Result<[u8; 4]> {
let mut bytes = [0; 4];
self.read_exact(&mut bytes)?;
Ok(bytes)
}
/// Convenience method to read a `[u8; 12]`.
#[inline]
fn read_12_bytes(&mut self) -> io::Result<[u8; 12]> {
let mut bytes = [0; 12];
self.read_exact(&mut bytes)?;
Ok(bytes)
}
/// Convenience method to read a `[u8; 32]`.
#[inline]
fn read_32_bytes(&mut self) -> io::Result<[u8; 32]> {
let mut bytes = [0; 32];
self.read_exact(&mut bytes)?;
Ok(bytes)
}
/// Convenience method to read a `[u8; 64]`.
#[inline]
fn read_64_bytes(&mut self) -> io::Result<[u8; 64]> {
let mut bytes = [0; 64];
self.read_exact(&mut bytes)?;
Ok(bytes)
}
}
/// Mark all types implementing `Read` as implementing the extension.
impl<R: io::Read + ?Sized> ReadZcashExt for R {}
/// Transform a Zcash-deserialized IPv6 address into a canonical Zebra IP address.
///
/// Zcash uses IPv6-mapped IPv4 addresses in its network protocol. Zebra converts
/// those addresses to `Ipv4Addr`s, for maximum compatibility with systems that
/// don't understand IPv6.
pub fn canonical_ip_addr(v6_addr: &Ipv6Addr) -> IpAddr {
use IpAddr::*;
// TODO: replace with `to_ipv4_mapped` when that stabilizes
// https://github.com/rust-lang/rust/issues/27709
match v6_addr.to_ipv4() {
// workaround for unstable `to_ipv4_mapped`
Some(v4_addr) if v4_addr.to_ipv6_mapped() == *v6_addr => V4(v4_addr),
Some(_) | None => V6(*v6_addr),
}
}
/// Transform a `SocketAddr` into a canonical Zebra `SocketAddr`, converting
/// IPv6-mapped IPv4 addresses, and removing IPv6 scope IDs and flow information.
///
/// See [`canonical_ip_addr`] for detailed info on IPv6-mapped IPv4 addresses.
pub fn canonical_socket_addr(socket_addr: impl Into<SocketAddr>) -> SocketAddr {
use SocketAddr::*;
let mut socket_addr = socket_addr.into();
if let V6(v6_socket_addr) = socket_addr {
let canonical_ip = canonical_ip_addr(v6_socket_addr.ip());
// creating a new SocketAddr removes scope IDs and flow information
socket_addr = SocketAddr::new(canonical_ip, socket_addr.port());
}
socket_addr
}