use std::{
cmp::min,
collections::BTreeMap,
io::{Error, ErrorKind},
};
use nix_compat_derive::{NixDeserialize, NixSerialize};
use num_enum::{FromPrimitive, IntoPrimitive, TryFromPrimitive};
use tokio::io::{AsyncReadExt, AsyncWriteExt};
use crate::wire;
use crate::wire::ProtocolVersion;
pub(crate) static WORKER_MAGIC_1: u64 = 0x6e697863; // "nixc"
pub(crate) static WORKER_MAGIC_2: u64 = 0x6478696f; // "dxio"
pub static STDERR_LAST: u64 = 0x616c7473; // "alts"
pub(crate) static STDERR_ERROR: u64 = 0x63787470; // "cxtp"
pub(crate) static STDERR_READ: u64 = 0x64617461; // "data"
/// | Nix version | Protocol |
/// |-----------------|----------|
/// | 0.11 | 1.02 |
/// | 0.12 | 1.04 |
/// | 0.13 | 1.05 |
/// | 0.14 | 1.05 |
/// | 0.15 | 1.05 |
/// | 0.16 | 1.06 |
/// | 1.0 | 1.10 |
/// | 1.1 | 1.11 |
/// | 1.2 | 1.12 |
/// | 1.3 - 1.5.3 | 1.13 |
/// | 1.6 - 1.10 | 1.14 |
/// | 1.11 - 1.11.16 | 1.15 |
/// | 2.0 - 2.0.4 | 1.20 |
/// | 2.1 - 2.3.18 | 1.21 |
/// | 2.4 - 2.6.1 | 1.32 |
/// | 2.7.0 | 1.33 |
/// | 2.8.0 - 2.14.1 | 1.34 |
/// | 2.15.0 - 2.19.4 | 1.35 |
/// | 2.20.0 - 2.22.0 | 1.37 |
static PROTOCOL_VERSION: ProtocolVersion = ProtocolVersion::from_parts(1, 37);
/// Max length of a Nix setting name/value. In bytes.
///
/// This value has been arbitrarily choosen after looking the nix.conf
/// manpage. Don't hesitate to increase it if it's too limiting.
pub static MAX_SETTING_SIZE: usize = 1024;
/// Worker Operation
///
/// These operations are encoded as unsigned 64 bits before being sent
/// to the wire. See the [read_op] and
/// [write_op] operations to serialize/deserialize the
/// operation on the wire.
///
/// Note: for now, we're using the Nix 2.20 operation description. The
/// operations marked as obsolete are obsolete for Nix 2.20, not
/// necessarily for Nix 2.3. We'll revisit this later on.
#[derive(
Clone, Debug, PartialEq, TryFromPrimitive, IntoPrimitive, NixDeserialize, NixSerialize,
)]
#[nix(try_from = "u64", into = "u64")]
#[repr(u64)]
pub enum Operation {
IsValidPath = 1,
HasSubstitutes = 3,
QueryPathHash = 4, // obsolete
QueryReferences = 5, // obsolete
QueryReferrers = 6,
AddToStore = 7,
AddTextToStore = 8, // obsolete since 1.25, Nix 3.0. Use WorkerProto::Op::AddToStore
BuildPaths = 9,
EnsurePath = 10,
AddTempRoot = 11,
AddIndirectRoot = 12,
SyncWithGC = 13,
FindRoots = 14,
ExportPath = 16, // obsolete
QueryDeriver = 18, // obsolete
SetOptions = 19,
CollectGarbage = 20,
QuerySubstitutablePathInfo = 21,
QueryDerivationOutputs = 22, // obsolete
QueryAllValidPaths = 23,
QueryFailedPaths = 24,
ClearFailedPaths = 25,
QueryPathInfo = 26,
ImportPaths = 27, // obsolete
QueryDerivationOutputNames = 28, // obsolete
QueryPathFromHashPart = 29,
QuerySubstitutablePathInfos = 30,
QueryValidPaths = 31,
QuerySubstitutablePaths = 32,
QueryValidDerivers = 33,
OptimiseStore = 34,
VerifyStore = 35,
BuildDerivation = 36,
AddSignatures = 37,
NarFromPath = 38,
AddToStoreNar = 39,
QueryMissing = 40,
QueryDerivationOutputMap = 41,
RegisterDrvOutput = 42,
QueryRealisation = 43,
AddMultipleToStore = 44,
AddBuildLog = 45,
BuildPathsWithResults = 46,
AddPermRoot = 47,
}
/// Log verbosity. In the Nix wire protocol, the client requests a
/// verbosity level to the daemon, which in turns does not produce any
/// log below this verbosity.
#[derive(
Debug, PartialEq, FromPrimitive, IntoPrimitive, NixDeserialize, NixSerialize, Default, Clone,
)]
#[nix(from = "u64", into = "u64")]
#[repr(u64)]
pub enum Verbosity {
#[default]
LvlError = 0,
LvlWarn = 1,
LvlNotice = 2,
LvlInfo = 3,
LvlTalkative = 4,
LvlChatty = 5,
LvlDebug = 6,
LvlVomit = 7,
}
/// Settings requested by the client. These settings are applied to a
/// connection to between the daemon and a client.
#[derive(Debug, PartialEq, NixDeserialize, NixSerialize, Default)]
pub struct ClientSettings {
pub keep_failed: bool,
pub keep_going: bool,
pub try_fallback: bool,
pub verbosity: Verbosity,
pub max_build_jobs: u64,
pub max_silent_time: u64,
pub use_build_hook: bool,
pub verbose_build: u64,
pub log_type: u64,
pub print_build_trace: u64,
pub build_cores: u64,
pub use_substitutes: bool,
/// Key/Value dictionary in charge of overriding the settings set
/// by the Nix config file.
///
/// Some settings can be safely overidden,
/// some other require the user running the Nix client to be part
/// of the trusted users group.
#[nix(version = "12..")]
pub overrides: BTreeMap<String, String>,
}
/// Performs the initial handshake the server is sending to a connecting client.
///
/// During the handshake, the client first send a magic u64, to which
/// the daemon needs to respond with another magic u64.
/// Then, the daemon retrieves the client version, and discards a bunch of now
/// obsolete data.
///
/// # Arguments
///
/// * conn: connection with the Nix client.
/// * nix_version: semantic version of the Nix daemon. "2.18.2" for
/// instance.
/// * trusted: trust level of the Nix client.
///
/// # Return
///
/// The protocol version to use for further comms, min(client_version, our_version).
pub async fn server_handshake_client<'a, RW: 'a>(
mut conn: &'a mut RW,
nix_version: &str,
trusted: Trust,
) -> std::io::Result<ProtocolVersion>
where
&'a mut RW: AsyncReadExt + AsyncWriteExt + Unpin,
{
let worker_magic_1 = conn.read_u64_le().await?;
if worker_magic_1 != WORKER_MAGIC_1 {
Err(std::io::Error::new(
ErrorKind::InvalidData,
format!("Incorrect worker magic number received: {}", worker_magic_1),
))
} else {
conn.write_u64_le(WORKER_MAGIC_2).await?;
conn.write_u64_le(PROTOCOL_VERSION.into()).await?;
conn.flush().await?;
let client_version = conn.read_u64_le().await?;
// Parse into ProtocolVersion.
let client_version: ProtocolVersion = client_version
.try_into()
.map_err(|e| Error::new(ErrorKind::Unsupported, e))?;
if client_version < ProtocolVersion::from_parts(1, 10) {
return Err(Error::new(
ErrorKind::Unsupported,
format!("The nix client version {} is too old", client_version),
));
}
let picked_version = min(PROTOCOL_VERSION, client_version);
if picked_version.minor() >= 14 {
// Obsolete CPU affinity.
let read_affinity = conn.read_u64_le().await?;
if read_affinity != 0 {
let _cpu_affinity = conn.read_u64_le().await?;
};
}
if picked_version.minor() >= 11 {
// Obsolete reserveSpace
let _reserve_space = conn.read_u64_le().await?;
}
if picked_version.minor() >= 33 {
// Nix version. We're plain lying, we're not Nix, but eh…
// Setting it to the 2.3 lineage. Not 100% sure this is a
// good idea.
wire::write_bytes(&mut conn, nix_version).await?;
conn.flush().await?;
}
if picked_version.minor() >= 35 {
write_worker_trust_level(&mut conn, trusted).await?;
}
Ok(picked_version)
}
}
/// Read a worker [Operation] from the wire.
pub async fn read_op<R: AsyncReadExt + Unpin>(r: &mut R) -> std::io::Result<Operation> {
let op_number = r.read_u64_le().await?;
Operation::try_from(op_number).map_err(|_| {
Error::new(
ErrorKind::InvalidData,
format!("Invalid OP number {}", op_number),
)
})
}
/// Write a worker [Operation] to the wire.
pub async fn write_op<W: AsyncWriteExt + Unpin>(w: &mut W, op: Operation) -> std::io::Result<()> {
let op: u64 = op.into();
w.write_u64(op).await
}
#[derive(Debug, PartialEq)]
pub enum Trust {
Trusted,
NotTrusted,
}
/// Write the worker [Trust] level to the wire.
///
/// Cpp Nix has a legacy third option: u8 0. This option is meant to
/// be used as a backward compatible measure. Since we're not
/// targetting protocol versions pre-dating the trust notion, we
/// decided not to implement it here.
pub async fn write_worker_trust_level<W>(conn: &mut W, t: Trust) -> std::io::Result<()>
where
W: AsyncReadExt + AsyncWriteExt + Unpin,
{
match t {
Trust::Trusted => conn.write_u64_le(1).await,
Trust::NotTrusted => conn.write_u64_le(2).await,
}
}
#[cfg(test)]
mod tests {
use super::*;
#[tokio::test]
async fn test_init_hanshake() {
let mut test_conn = tokio_test::io::Builder::new()
.read(&WORKER_MAGIC_1.to_le_bytes())
.write(&WORKER_MAGIC_2.to_le_bytes())
.write(&[37, 1, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])
// Let's say the client is in sync with the daemon
// protocol-wise
.read(&[37, 1, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])
// cpu affinity
.read(&[0; 8])
// reservespace
.read(&[0; 8])
// version (size)
.write(&[0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])
// version (data == 2.18.2 + padding)
.write(&[50, 46, 49, 56, 46, 50, 0, 0])
// Trusted (1 == client trusted
.write(&[1, 0, 0, 0, 0, 0, 0, 0])
.build();
let picked_version = server_handshake_client(&mut test_conn, "2.18.2", Trust::Trusted)
.await
.unwrap();
assert_eq!(picked_version, PROTOCOL_VERSION)
}
#[tokio::test]
async fn test_init_hanshake_with_newer_client_should_use_older_version() {
let mut test_conn = tokio_test::io::Builder::new()
.read(&WORKER_MAGIC_1.to_le_bytes())
.write(&WORKER_MAGIC_2.to_le_bytes())
.write(&[37, 1, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])
// Client is newer than us.
.read(&[38, 1, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])
// cpu affinity
.read(&[0; 8])
// reservespace
.read(&[0; 8])
// version (size)
.write(&[0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])
// version (data == 2.18.2 + padding)
.write(&[50, 46, 49, 56, 46, 50, 0, 0])
// Trusted (1 == client trusted
.write(&[1, 0, 0, 0, 0, 0, 0, 0])
.build();
let picked_version = server_handshake_client(&mut test_conn, "2.18.2", Trust::Trusted)
.await
.unwrap();
assert_eq!(picked_version, PROTOCOL_VERSION)
}
#[tokio::test]
async fn test_init_hanshake_with_older_client_should_use_older_version() {
let mut test_conn = tokio_test::io::Builder::new()
.read(&WORKER_MAGIC_1.to_le_bytes())
.write(&WORKER_MAGIC_2.to_le_bytes())
.write(&[37, 1, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])
// Client is newer than us.
.read(&[24, 1, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])
// cpu affinity
.read(&[0; 8])
// reservespace
.read(&[0; 8])
// NOTE: we are not writing version and trust since the client is too old.
// version (size)
//.write(&[0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])
// version (data == 2.18.2 + padding)
//.write(&[50, 46, 49, 56, 46, 50, 0, 0])
// Trusted (1 == client trusted
//.write(&[1, 0, 0, 0, 0, 0, 0, 0])
.build();
let picked_version = server_handshake_client(&mut test_conn, "2.18.2", Trust::Trusted)
.await
.unwrap();
assert_eq!(picked_version, ProtocolVersion::from_parts(1, 24))
}
}
