compression ????!?!???

Author: nothendev

Cargo.lock

@@ -9,6 +9,7 @@ resolver = "2"
 
 [workspace.dependencies]
 oxcr_protocol.path = "protocol"
+oxcr_cli.path = "cli"
 tokio = { version = "1", features = [ "macros", "full", "rt", "sync" ] }
 derive_more.version = "0.99.17"
 tracing.version = "0"
@@ -17,3 +18,4 @@ bytes = { version = "1", features = [ "serde" ] }
 bevy = { version = "0.11.2", features = ["multi-threaded"], default-features = false }
 rayon = "1"
 itertools = "0"
+flate2 = "1"

Cargo.toml

@@ -32,6 +32,7 @@ pub enum CliCommand {
     Decode(ByteInput),
     Help,
     VarInt(ByteInput),
+    Decompress(ByteInput),
 }
 
 #[derive(Debug, Clone)]
@@ -46,10 +47,11 @@ pub enum Flag {
     Help,
     Decode(ByteInput),
     VarInt(ByteInput),
+    Decompress(ByteInput),
 }
 
 #[derive(Debug)]
-enum FlagName<'a> {
+pub enum FlagName<'a> {
     Short(&'a str),
     Long(&'a str),
 }
@@ -90,7 +92,7 @@ fn byte_input(input: &str) -> ByteInput {
 }
 
 #[parser(extras = Extra)]
-fn flag_list(input: &str) -> Vec<FlagName<'a>> {
+pub fn flag_list(input: &str) -> Vec<FlagName<'a>> {
     if input.offset.saturating_sub(1) >= input.input.len() {
         return Ok(vec![]);
     }
@@ -134,6 +136,11 @@ fn flags(input: &str) -> Vec<Flag> {
 
                         Flag::Decode(byte_input(input)?)
                     }
+                    FlagName::Short("c") | FlagName::Long("decompress") => {
+                        one_of(" =")(input)?;
+
+                        Flag::Decompress(byte_input(input)?)
+                    }
                     FlagName::Short("V") | FlagName::Long("varint") => {
                         one_of(" =")(input)?;
 
@@ -160,6 +167,7 @@ fn flags_handle<'a>(
             Flag::Help => cli.command = CliCommand::Help,
             Flag::Decode(input) => cli.command = CliCommand::Decode(input),
             Flag::VarInt(input) => cli.command = CliCommand::VarInt(input),
+            Flag::Decompress(input) => cli.command = CliCommand::Decompress(input),
         }
     }
     try { flags(input)?.into_iter().for_each(|flag| handle(cli, flag)) }

cli/src/cli.rs

@@ -1,4 +1,4 @@
-use std::{ops::Range, str::FromStr};
+use std::{borrow::Cow, num::ParseIntError, ops::Range, str::FromStr};
 
 use oxcr_protocol::{
     aott,
@@ -17,6 +17,8 @@ pub enum ParseError {
         found: char,
         #[label = "here"]
         at: SourceSpan,
+        #[help]
+        help: Option<Cow<'static, str>>,
     },
     #[error("unexpected end of input{}", .expected.as_ref().map(|expectation| format!(", expected {expectation}")).unwrap_or_else(String::new))]
     #[diagnostic(
@@ -44,6 +46,18 @@ pub enum ParseError {
         #[label = "here"]
         at: SourceSpan,
     },
+    #[error("expected a number with radix {radix}, got {actual}")]
+    #[diagnostic(code(cli::expected_number))]
+    ExpectedNumber {
+        radix: u32,
+        actual: String,
+        #[label = "here"]
+        at: SourceSpan,
+        #[help]
+        help: Option<Cow<'static, str>>,
+        #[source]
+        error: ParseIntError,
+    },
 }
 
 #[derive(Debug, thiserror::Error)]
@@ -79,6 +93,7 @@ impl<'a> aott::error::Error<&'a str> for ParseError {
             expected: Expectation::AnyOf(expected),
             found: found.into_clone(),
             at: span.into(),
+            help: None,
         }
     }
 
@@ -87,6 +102,7 @@ impl<'a> aott::error::Error<&'a str> for ParseError {
             expected: Expectation::EndOfInput,
             found: found.into_clone(),
             at: span.into(),
+            help: None,
         }
     }
 }

cli/src/error.rs

@@ -0,0 +1,6 @@
+#![feature(iterator_try_collect, try_blocks)]
+
+mod cli;
+pub use cli::{flag_list, Extra, FlagName};
+mod error;
+pub use error::*;

cli/src/lib.rs

@@ -20,7 +20,7 @@ mod cli;
 mod error;
 
 fn run(_path: String, args: &str) -> Result<(), Report> {
-    let tsub_guard = tracing_subscriber::fmt()
+    let tracing_set_default_level = tracing_subscriber::fmt()
         .pretty()
         .with_env_filter(EnvFilter::from_env("OXCR_LOG"))
         .finish()
@@ -30,9 +30,9 @@ fn run(_path: String, args: &str) -> Result<(), Report> {
         .parse(args)
         .map_err(|parse_error| Report::new(parse_error).with_source_code(args.to_owned()))?;
 
-    drop(tsub_guard);
+    drop(tracing_set_default_level);
 
-    let _tsub_guard = tracing_subscriber::fmt()
+    let _tracing_set_real_level = tracing_subscriber::fmt()
         .with_env_filter(cli.level.to_string())
         .pretty()
         .set_default();
@@ -43,17 +43,15 @@ fn run(_path: String, args: &str) -> Result<(), Report> {
         CliCommand::Help => help(),
         CliCommand::Decode(inp) => {
             let bytes = read_byte_input(inp)?;
-            let spack = SerializedPacket {
-                length: LoginPlay::ID.length_of() + bytes.len(),
-                data: bytes,
-                id: LoginPlay::ID,
-            };
+            debug!("{bytes:?}");
+            let spack = SerializedPacket::deserialize.parse(&bytes)?;
             let deserialized: LoginPlay = spack.try_deserialize(LoginPlay::STATE)?;
 
             println!("{:#?}", deserialized);
         }
         CliCommand::VarInt(inp) => {
             let bytes = read_byte_input(inp)?;
+
             println!(
                 "{:#?}",
                 VarInt::<i64>::deserialize
@@ -62,7 +60,8 @@ fn run(_path: String, args: &str) -> Result<(), Report> {
                     .map_err(reconcile(bytes))?
             );
         }
-    }
+        CliCommand::Decompress(inp) => todo!(),
+    };
 
     Ok(())
 }

cli/src/main.rs

@@ -21,3 +21,5 @@ uuid = { version = "1.4.1", features = ["v3"] }
 bitflags = "2.4.0"
 miette = { version = "5.10.0", features = ["fancy"] }
 indexmap = { version = "2.0.0", features = ["serde"] }
+
+flate2.workspace = true

protocol/Cargo.toml

@@ -156,6 +156,7 @@ impl PlayerNet {
 
             return Err::<!, crate::error::Error>(e);
         });
+
         let recv_task = tokio::spawn(async move {
             async {
                 let mut buf = BytesMut::new();

protocol/src/lib.rs

@@ -119,6 +119,102 @@ impl Serialize for SerializedPacket {
     }
 }
 
+#[derive(Debug, Clone)]
+pub struct SerializedPacketCompressed {
+    pub length: usize,
+    pub data_length: usize,
+    pub id: Compress<super::VarInt, Zlib>,
+    pub data: Compress<Bytes, Zlib>,
+}
+
+impl SerializedPacketCompressed {
+    pub fn new<P: Packet + Serialize>(packet: P) -> Result<Self, Error> {
+        Self::new_ref(&packet)
+    }
+
+    pub fn new_ref<P: Packet + Serialize + ?Sized>(packet: &P) -> Result<Self, Error> {
+        try {
+            let data = packet.serialize()?;
+            let id = P::ID;
+            let data_length = id.length_of() + data.len();
+            let datalength = VarInt::<i32>(data_length.try_into().unwrap());
+            let length = datalength.length_of() + Compress(datalength, Zlib).serialize()?.len();
+            Self {
+                length,
+                data_length,
+                id: Compress(id, Zlib),
+                data: Compress(data, Zlib),
+            }
+        }
+    }
+
+    pub fn try_deserialize<P: Packet + Deserialize<Context = PacketContext>>(
+        &self,
+        state: State,
+    ) -> Result<P, Error> {
+        let context = PacketContext {
+            id: self.id.0,
+            state,
+        };
+
+        P::deserialize
+            .parse_with_context(self.data.0.as_ref(), context)
+            .map_err(|e| match e {
+                Error::Ser(error) => Error::SerSrc(WithSource {
+                    source: BytesSource::new(
+                        self.data.0.clone(),
+                        Some(format!("packet_0x{:x}.bin", self.id.0 .0)),
+                    ),
+                    span: error.span,
+                    kind: error.kind,
+                }),
+                e => e,
+            })
+    }
+}
+
+impl Deserialize for SerializedPacketCompressed {
+    #[parser(extras = "Extra<Self::Context>")]
+    fn deserialize(input: &[u8]) -> Self {
+        try {
+            let packet_length_varint = VarInt::<i32>::deserialize(input)?;
+            assert!(packet_length_varint.0 >= 0);
+            let packet_length = packet_length_varint.0 as usize;
+            let data_length_varint = VarInt::<i32>::deserialize(input)?;
+            assert!(data_length_varint.0 >= 0);
+            let data_length = data_length_varint.0 as usize;
+            let id: Compress<VarInt<i32>, Zlib> = Compress::decompress(Bytes::copy_from_slice(
+                input.input.slice_from(input.offset..),
+            ))?;
+            let data = Compress::decompress(Bytes::from(
+                take(data_length - id.0.length_of()).parse_with(input)?,
+            ))?;
+            Self {
+                length: packet_length,
+                data_length,
+                id,
+                data,
+            }
+        }
+    }
+}
+
+impl Serialize for SerializedPacketCompressed {
+    fn serialize_to(&self, buf: &mut BytesMut) -> Result<(), Error> {
+        let length = VarInt::<i32>(self.length.try_into().map_err(|_| Error::VarIntTooBig)?);
+        length.serialize_to(buf)?;
+        let data_length = VarInt::<i32>(
+            self.data_length
+                .try_into()
+                .map_err(|_| Error::VarIntTooBig)?,
+        );
+        data_length.serialize_to(buf)?;
+        self.id.serialize_to(buf)?;
+        self.data.serialize_to(buf)?;
+        Ok(())
+    }
+}
+
 #[derive(Debug, Clone)]
 pub struct PluginMessage {
     pub channel: Identifier,

protocol/src/model/packets.rs

@@ -196,3 +196,34 @@ impl Packet for SetDefaultSpawnPosition {
     const ID: crate::model::VarInt = VarInt(0x50);
     const STATE: crate::model::State = State::Play;
 }
+
+/// This packet tells the client that it should enable support for the feature flags listed in the `feature_flags` field.
+/// Note that adding arbitrary identifiers (instead of the constants under this struct,
+/// like `FEATURE_VANILLA` or `FEATURE_BUNDLE`) to the list may cause the client to explode.
+///
+/// # Info
+/// Packet ID: 0x6b
+/// State: Play
+/// Bound to: Client
+///
+/// # Layout
+/// Total Features: VarInt ;; number of elements in the next array
+/// Feature Flags: Array<Identifier>
+#[derive(Debug, Clone)]
+pub struct FeatureFlags {
+    pub feature_flags: Array<Identifier>,
+}
+
+impl Packet for FeatureFlags {
+    const ID: crate::model::VarInt = VarInt(0x6b);
+    const STATE: crate::model::State = State::Play;
+}
+
+impl_ser!(|PacketContext| FeatureFlags => [feature_flags]);
+
+impl FeatureFlags {
+    /// A feature flag that enables all vanilla features in the notchian client.
+    pub const FEATURE_VANILLA: Identifier = Identifier::new_static(Namespace::Minecraft, "vanilla");
+    /// A feature flag that enables support for bundles in the notchian client.
+    pub const FEATURE_BUNDLE: Identifier = Identifier::new_static(Namespace::Minecraft, "bundle");
+}