diff options
Diffstat (limited to 'tvix/nix-compat/src/nix_daemon/worker_protocol.rs')
| -rw-r--r-- | tvix/nix-compat/src/nix_daemon/worker_protocol.rs | 434 |
1 files changed, 434 insertions, 0 deletions
diff --git a/tvix/nix-compat/src/nix_daemon/worker_protocol.rs b/tvix/nix-compat/src/nix_daemon/worker_protocol.rs new file mode 100644 index 0000000000..7e3adc0db2 --- /dev/null +++ b/tvix/nix-compat/src/nix_daemon/worker_protocol.rs @@ -0,0 +1,434 @@ +use std::{ + collections::HashMap, + io::{Error, ErrorKind}, +}; + +use enum_primitive_derive::Primitive; +use num_traits::{FromPrimitive, ToPrimitive}; +use tokio::io::{AsyncReadExt, AsyncWriteExt}; + +use crate::wire; + +use super::ProtocolVersion; + +static WORKER_MAGIC_1: u64 = 0x6e697863; // "nixc" +static WORKER_MAGIC_2: u64 = 0x6478696f; // "dxio" +pub static STDERR_LAST: u64 = 0x616c7473; // "alts" + +/// | 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(Debug, PartialEq, Primitive)] +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, Primitive)] +pub enum Verbosity { + 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)] +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 verbose_build: bool, + 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. + pub overrides: HashMap<String, String>, +} + +/// Reads the client settings from the wire. +/// +/// Note: this function **only** reads the settings. It does not +/// manage the log state with the daemon. You'll have to do that on +/// your own. A minimal log implementation will consist in sending +/// back [STDERR_LAST] to the client after reading the client +/// settings. +/// +/// FUTUREWORK: write serialization. +pub async fn read_client_settings<R: AsyncReadExt + Unpin>( + r: &mut R, + client_version: ProtocolVersion, +) -> std::io::Result<ClientSettings> { + let keep_failed = r.read_u64_le().await? != 0; + let keep_going = r.read_u64_le().await? != 0; + let try_fallback = r.read_u64_le().await? != 0; + let verbosity_uint = r.read_u64_le().await?; + let verbosity = Verbosity::from_u64(verbosity_uint).ok_or_else(|| { + Error::new( + ErrorKind::InvalidData, + format!("Can't convert integer {} to verbosity", verbosity_uint), + ) + })?; + let max_build_jobs = r.read_u64_le().await?; + let max_silent_time = r.read_u64_le().await?; + _ = r.read_u64_le().await?; // obsolete useBuildHook + let verbose_build = r.read_u64_le().await? != 0; + _ = r.read_u64_le().await?; // obsolete logType + _ = r.read_u64_le().await?; // obsolete printBuildTrace + let build_cores = r.read_u64_le().await?; + let use_substitutes = r.read_u64_le().await? != 0; + let mut overrides = HashMap::new(); + if client_version.minor() >= 12 { + let num_overrides = r.read_u64_le().await?; + for _ in 0..num_overrides { + let name = wire::read_string(r, 0..=MAX_SETTING_SIZE).await?; + let value = wire::read_string(r, 0..=MAX_SETTING_SIZE).await?; + overrides.insert(name, value); + } + } + Ok(ClientSettings { + keep_failed, + keep_going, + try_fallback, + verbosity, + max_build_jobs, + max_silent_time, + verbose_build, + build_cores, + use_substitutes, + overrides, + }) +} + +/// 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 of the client. +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), + )); + } + if client_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 client_version.minor() >= 11 { + // Obsolete reserveSpace + let _reserve_space = conn.read_u64_le().await?; + } + if client_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 client_version.minor() >= 35 { + write_worker_trust_level(&mut conn, trusted).await?; + } + Ok(client_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::from_u64(op_number).ok_or(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 = Operation::to_u64(op).ok_or(Error::new( + ErrorKind::Other, + format!("Can't convert the OP {:?} to u64", op), + ))?; + 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::*; + use hex_literal::hex; + use tokio_test::io::Builder; + + #[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 client_version = server_handshake_client(&mut test_conn, "2.18.2", Trust::Trusted) + .await + .unwrap(); + + assert_eq!(client_version, PROTOCOL_VERSION) + } + + #[tokio::test] + async fn test_read_client_settings_without_overrides() { + // Client settings bits captured from a Nix 2.3.17 run w/ sockdump (protocol version 21). + let wire_bits = hex!( + "00 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 02 00 00 00 00 00 00 00 \ + 10 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 01 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 01 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00" + ); + let mut mock = Builder::new().read(&wire_bits).build(); + let settings = read_client_settings(&mut mock, ProtocolVersion::from_parts(1, 21)) + .await + .expect("should parse"); + let expected = ClientSettings { + keep_failed: false, + keep_going: false, + try_fallback: false, + verbosity: Verbosity::LvlNotice, + max_build_jobs: 16, + max_silent_time: 0, + verbose_build: false, + build_cores: 0, + use_substitutes: true, + overrides: HashMap::new(), + }; + assert_eq!(settings, expected); + } + + #[tokio::test] + async fn test_read_client_settings_with_overrides() { + // Client settings bits captured from a Nix 2.3.17 run w/ sockdump (protocol version 21). + let wire_bits = hex!( + "00 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 02 00 00 00 00 00 00 00 \ + 10 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 01 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 00 00 00 00 00 00 00 00 \ + 01 00 00 00 00 00 00 00 \ + 02 00 00 00 00 00 00 00 \ + 0c 00 00 00 00 00 00 00 \ + 61 6c 6c 6f 77 65 64 2d \ + 75 72 69 73 00 00 00 00 \ + 1e 00 00 00 00 00 00 00 \ + 68 74 74 70 73 3a 2f 2f \ + 62 6f 72 64 65 61 75 78 \ + 2e 67 75 69 78 2e 67 6e \ + 75 2e 6f 72 67 2f 00 00 \ + 0d 00 00 00 00 00 00 00 \ + 61 6c 6c 6f 77 65 64 2d \ + 75 73 65 72 73 00 00 00 \ + 0b 00 00 00 00 00 00 00 \ + 6a 65 61 6e 20 70 69 65 \ + 72 72 65 00 00 00 00 00" + ); + let mut mock = Builder::new().read(&wire_bits).build(); + let settings = read_client_settings(&mut mock, ProtocolVersion::from_parts(1, 21)) + .await + .expect("should parse"); + let overrides = HashMap::from([ + ( + String::from("allowed-uris"), + String::from("https://bordeaux.guix.gnu.org/"), + ), + (String::from("allowed-users"), String::from("jean pierre")), + ]); + let expected = ClientSettings { + keep_failed: false, + keep_going: false, + try_fallback: false, + verbosity: Verbosity::LvlNotice, + max_build_jobs: 16, + max_silent_time: 0, + verbose_build: false, + build_cores: 0, + use_substitutes: true, + overrides, + }; + assert_eq!(settings, expected); + } +} |