common.rs

// Copied from aquatic_udp_protocol 0.9.0 by Joakim Frostegard (greatest-ape).
// Source:     https://crates.io/crates/aquatic_udp_protocol/0.9.0
// Repository: https://github.com/greatest-ape/aquatic
// License:    Apache License, Version 2.0 (https://www.apache.org/licenses/LICENSE-2.0)
//
// This in-house crate started from the aquatic 0.9.0 sources that were previously vendored
// under packages/aquatic-udp-protocol.
use std::fmt::Debug;
use std::net::{Ipv4Addr, Ipv6Addr};
use std::num::NonZeroU16;

pub(crate) use torrust_peer_id::PeerId;
use zerocopy::byteorder::network_endian::{I32, I64, U16, U32};
use zerocopy::{FromBytes, Immutable, IntoBytes};

pub trait Ip: Clone + Copy + Debug + PartialEq + Eq + std::hash::Hash + IntoBytes + Immutable {}

#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug, IntoBytes, FromBytes, Immutable)]
#[repr(transparent)]
// Intentionally kept in `common`: this protocol-level wire type mirrors
// `bittorrent-primitives::InfoHash` and may be unified across packages later.
pub struct InfoHash(pub [u8; 20]);

#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug, IntoBytes, FromBytes, Immutable)]
#[repr(transparent)]
pub struct ConnectionId(pub I64);

impl ConnectionId {
    pub fn new(v: i64) -> Self {
        Self(I64::new(v))
    }
}

#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug, IntoBytes, FromBytes, Immutable)]
#[repr(transparent)]
pub struct TransactionId(pub I32);

impl TransactionId {
    pub fn new(v: i32) -> Self {
        Self(I32::new(v))
    }
}

#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug, IntoBytes, FromBytes, Immutable)]
#[repr(transparent)]
// Intentionally kept in `common`: this mirrors
// `packages/primitives/src/number_of_bytes.rs` and HTTP protocol byte counters,
// but remains UDP-local so protocol wire representations can evolve
// independently per protocol.
pub struct NumberOfBytes(pub I64);

impl NumberOfBytes {
    pub fn new(v: i64) -> Self {
        Self(I64::new(v))
    }
}

#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug, IntoBytes, FromBytes, Immutable)]
#[repr(transparent)]
pub struct NumberOfPeers(pub I32);

impl NumberOfPeers {
    pub fn new(v: i32) -> Self {
        Self(I32::new(v))
    }
}

#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug, IntoBytes, FromBytes, Immutable)]
#[repr(transparent)]
pub struct NumberOfDownloads(pub I32);

impl NumberOfDownloads {
    pub fn new(v: i32) -> Self {
        Self(I32::new(v))
    }
}

#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug, IntoBytes, FromBytes, Immutable)]
#[repr(transparent)]
pub struct Port(pub U16);

impl Port {
    pub fn new(v: NonZeroU16) -> Self {
        Self(U16::new(v.into()))
    }
}

#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug, IntoBytes, FromBytes, Immutable)]
#[repr(transparent)]
pub struct PeerKey(pub I32);

impl PeerKey {
    pub fn new(v: i32) -> Self {
        Self(I32::new(v))
    }
}

#[derive(PartialEq, Eq, Clone, Copy, Debug, Hash, IntoBytes, FromBytes, Immutable)]
#[repr(C, packed)]
pub struct ResponsePeer<I: Ip> {
    pub ip_address: I,
    pub port: Port,
}

#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug, IntoBytes, FromBytes, Immutable)]
#[repr(transparent)]
pub struct Ipv4AddrBytes(pub [u8; 4]);

impl Ip for Ipv4AddrBytes {}

impl From<Ipv4AddrBytes> for Ipv4Addr {
    fn from(val: Ipv4AddrBytes) -> Self {
        Ipv4Addr::from(val.0)
    }
}

impl From<Ipv4Addr> for Ipv4AddrBytes {
    fn from(val: Ipv4Addr) -> Self {
        Ipv4AddrBytes(val.octets())
    }
}

#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug, IntoBytes, FromBytes, Immutable)]
#[repr(transparent)]
pub struct Ipv6AddrBytes(pub [u8; 16]);

impl Ip for Ipv6AddrBytes {}

impl From<Ipv6AddrBytes> for Ipv6Addr {
    fn from(val: Ipv6AddrBytes) -> Self {
        Ipv6Addr::from(val.0)
    }
}

impl From<Ipv6Addr> for Ipv6AddrBytes {
    fn from(val: Ipv6Addr) -> Self {
        Ipv6AddrBytes(val.octets())
    }
}

pub fn read_i32_ne(bytes: &mut impl ::std::io::Read) -> ::std::io::Result<I32> {
    let mut tmp = [0u8; 4];

    bytes.read_exact(&mut tmp)?;

    Ok(I32::from_bytes(tmp))
}

pub fn read_i64_ne(bytes: &mut impl ::std::io::Read) -> ::std::io::Result<I64> {
    let mut tmp = [0u8; 8];

    bytes.read_exact(&mut tmp)?;

    Ok(I64::from_bytes(tmp))
}

pub fn read_u16_ne(bytes: &mut impl ::std::io::Read) -> ::std::io::Result<U16> {
    let mut tmp = [0u8; 2];

    bytes.read_exact(&mut tmp)?;

    Ok(U16::from_bytes(tmp))
}

pub fn read_u32_ne(bytes: &mut impl ::std::io::Read) -> ::std::io::Result<U32> {
    let mut tmp = [0u8; 4];

    bytes.read_exact(&mut tmp)?;

    Ok(U32::from_bytes(tmp))
}

pub fn invalid_data() -> ::std::io::Error {
    ::std::io::Error::new(::std::io::ErrorKind::InvalidData, "invalid data")
}

#[cfg(test)]
impl quickcheck::Arbitrary for InfoHash {
    fn arbitrary(g: &mut quickcheck::Gen) -> Self {
        let mut bytes = [0u8; 20];

        for byte in bytes.iter_mut() {
            *byte = u8::arbitrary(g);
        }

        Self(bytes)
    }
}

#[cfg(test)]
impl<I: Ip + quickcheck::Arbitrary> quickcheck::Arbitrary for ResponsePeer<I> {
    fn arbitrary(g: &mut quickcheck::Gen) -> Self {
        Self {
            ip_address: quickcheck::Arbitrary::arbitrary(g),
            port: Port(u16::arbitrary(g).into()),
        }
    }
}