WIP WIA/RVZ & more

.github/workflows/build.yaml

@@ -2,59 +2,174 @@ name: Build
 
 on: [ push, pull_request ]
 
+env:
+  BUILD_PROFILE: release-lto
+  CARGO_BIN_NAME: nodtool
+  CARGO_TARGET_DIR: target
+
 jobs:
   check:
     name: Check
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        toolchain: [ stable, 1.51.0, nightly ]
+        toolchain: [ stable, 1.56.0, nightly ]
     env:
       RUSTFLAGS: -D warnings
     steps:
-      - uses: actions/checkout@v2
+      - name: Checkout
-      - uses: actions-rs/toolchain@v1
+        uses: actions/checkout@v3
+      - name: Setup Rust toolchain
+        uses: dtolnay/rust-toolchain@master
         with:
-          profile: minimal
           toolchain: ${{ matrix.toolchain }}
-          override: true
           components: rustfmt, clippy
+      - name: Cargo check
+        run: cargo check --all-features --all-targets
+      - name: Cargo clippy
+        run: cargo clippy --all-features --all-targets
+
+  fmt:
+    name: Format
+    runs-on: ubuntu-latest
+    env:
+      RUSTFLAGS: -D warnings
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Setup Rust toolchain
+        # We use nightly options in rustfmt.toml
+        uses: dtolnay/rust-toolchain@nightly
+        with:
+          components: rustfmt
+      - name: Cargo fmt
+        run: cargo fmt --all --check
+
+  deny:
+    name: Deny
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        checks:
+          - advisories
+          - bans licenses sources
+    # Prevent new advisories from failing CI
+    continue-on-error: ${{ matrix.checks == 'advisories' }}
+    steps:
+      - uses: actions/checkout@v3
       - uses: EmbarkStudios/cargo-deny-action@v1
-      - uses: actions-rs/cargo@v1
         with:
-          command: check
+          command: check ${{ matrix.checks }}
-          args: --all-features
+
-      - uses: actions-rs/cargo@v1
+  test:
-        with:
+    name: Test
-          command: clippy
+    strategy:
-          args: --all-features
+      matrix:
+        platform: [ ubuntu-latest, windows-latest, macos-latest ]
+      fail-fast: false
+    runs-on: ${{ matrix.platform }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Setup Rust toolchain
+        uses: dtolnay/rust-toolchain@stable
+      - name: Cargo test
+        run: cargo test --release --all-features
 
   build:
     name: Build
     strategy:
       matrix:
-        platform: [ ubuntu-latest, macos-latest, windows-latest ]
+        include:
-        toolchain: [ stable, 1.51.0, nightly ]
+          - platform: ubuntu-latest
+            target: x86_64-unknown-linux-musl
+            name: linux-x86_64
+            build: zigbuild
+            features: asm
+          - platform: ubuntu-latest
+            target: i686-unknown-linux-musl
+            name: linux-i686
+            build: zigbuild
+            features: asm
+          - platform: ubuntu-latest
+            target: aarch64-unknown-linux-musl
+            name: linux-aarch64
+            build: zigbuild
+            features: nightly
+          - platform: ubuntu-latest
+            target: armv7-unknown-linux-musleabi
+            name: linux-armv7l
+            build: zigbuild
+            features: default
+          - platform: windows-latest
+            target: x86_64-pc-windows-msvc
+            name: windows-x86_64
+            build: build
+            features: asm
+          - platform: windows-latest
+            target: aarch64-pc-windows-msvc
+            name: windows-arm64
+            build: build
+            features: nightly
+          - platform: macos-latest
+            target: x86_64-apple-darwin
+            name: macos-x86_64
+            build: build
+            features: asm
+          - platform: macos-latest
+            target: aarch64-apple-darwin
+            name: macos-arm64
+            build: build
+            features: nightly
       fail-fast: false
     runs-on: ${{ matrix.platform }}
     steps:
-      - uses: actions/checkout@v2
+      - name: Checkout
-      - uses: actions-rs/toolchain@v1
+        uses: actions/checkout@v3
+      - name: Install dependencies
+        if: matrix.packages != ''
+        run: |
+          sudo apt-get -y update
+          sudo apt-get -y install ${{ matrix.packages }}
+      - name: Install cargo-zigbuild
+        if: matrix.build == 'zigbuild'
+        run: pip install ziglang==0.11.0 cargo-zigbuild==0.18.3
+      - name: Setup Rust toolchain
+        uses: dtolnay/rust-toolchain@nightly
         with:
-          profile: minimal
+          targets: ${{ matrix.target }}
-          toolchain: ${{ matrix.toolchain }}
+      - name: Cargo build
-          override: true
+        run: cargo ${{ matrix.build }} --profile ${{ env.BUILD_PROFILE }} --target ${{ matrix.target }} --bin ${{ env.CARGO_BIN_NAME }} --features ${{ matrix.features }}
-      - uses: actions-rs/cargo@v1
+      - name: Upload artifacts
+        uses: actions/upload-artifact@v3
         with:
-          command: test
+          name: ${{ matrix.name }}
-          args: --release --all-features
-      - uses: actions-rs/cargo@v1
-        with:
-          command: build
-          args: --release --all-features
-      - uses: actions/upload-artifact@v2
-        with:
-          name: ${{ matrix.platform }}-${{ matrix.toolchain }}
           path: |
-            target/release/nodtool
+            ${{ env.CARGO_TARGET_DIR }}/${{ env.BUILD_PROFILE }}/${{ env.CARGO_BIN_NAME }}
-            target/release/nodtool.exe
+            ${{ env.CARGO_TARGET_DIR }}/${{ env.BUILD_PROFILE }}/${{ env.CARGO_BIN_NAME }}.exe
+            ${{ env.CARGO_TARGET_DIR }}/${{ matrix.target }}/${{ env.BUILD_PROFILE }}/${{ env.CARGO_BIN_NAME }}
+            ${{ env.CARGO_TARGET_DIR }}/${{ matrix.target }}/${{ env.BUILD_PROFILE }}/${{ env.CARGO_BIN_NAME }}.exe
+          if-no-files-found: error
+
+  release:
+    name: Release
+    if: startsWith(github.ref, 'refs/tags/')
+    runs-on: ubuntu-latest
+    needs: [ build ]
+    steps:
+      - name: Download artifacts
+        uses: actions/download-artifact@v3
+        with:
+          path: artifacts
+      - name: Rename artifacts
+        working-directory: artifacts
+        run: |
+          mkdir ../out
+          for i in */*/$BUILD_PROFILE/$CARGO_BIN_NAME*; do
+            mv "$i" "../out/$(sed -E "s/([^/]+)\/[^/]+\/$BUILD_PROFILE\/($CARGO_BIN_NAME)/\2-\1/" <<< "$i")"
+          done
+          ls -R ../out
+      - name: Release
+        uses: softprops/action-gh-release@v1
+        with:
+          files: out/*

Cargo.toml

@@ -1,7 +1,8 @@
 [package]
 name = "nod"
-version = "0.1.2"
+version = "0.2.0"
-edition = "2018"
+edition = "2021"
+rust-version = "1.56.0"
 authors = ["Luke Street <luke@street.dev>"]
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/encounter/nod-rs"
@@ -17,16 +18,33 @@ categories = ["command-line-utilities", "parser-implementations"]
 name = "nodtool"
 path = "src/bin.rs"
 
-[profile.release]
+[profile.release-lto]
-lto = true
+inherits = "release"
+lto = "thin"
+strip = "debuginfo"
+
+[features]
+default = ["compress-bzip2", "compress-zstd"] #, "compress-lzma"
+asm = ["md-5/asm", "sha1/asm"]
+compress-bzip2 = ["bzip2"]
+compress-zstd = ["zstd"]
+#compress-lzma = ["xz2"]
+nightly = ["crc32fast/nightly"]
 
 [dependencies]
-aes = "0.7.5"
+aes = "0.8.3"
-anyhow = "1.0.53"
+argh = "0.1.12"
-binrw = "0.8.4"
+argh_derive = "0.1.12"
-block-modes = "0.8.1"
+base16ct = "0.2.0"
-clap = "2.34.0"
+binrw = "0.13.3"
-encoding_rs = "0.8.30"
+bytemuck = "1.14.1"
+bzip2 = { version = "0.4.4", optional = true }
+cbc = "0.1.2"
+crc32fast = "1.3.2"
+encoding_rs = "0.8.33"
 file-size = "1.0.3"
-sha-1 = "0.10.0"
+md-5 = "0.10.6"
-thiserror = "1.0.30"
+sha1 = "0.10.6"
+thiserror = "1.0.56"
+xz2 = { version = "0.1.7", optional = true }
+zstd = { version = "0.13.0", optional = true }

README.md

@@ -14,7 +14,9 @@ Based on the C++ library [nod](https://github.com/AxioDL/nod),
 but does not currently support authoring.
 
 Currently supported file formats:
-- ISO
+- ISO (GCM)
+- WIA / RVZ
+- WBFS
 - NFS (Wii U VC files, e.g. `hif_000000.nfs`)
 
 ### CLI tool
@@ -34,20 +36,28 @@ nodtool extract /path/to/game/content/hif_000000.nfs [outdir]
 ### Library example
 
 Opening a disc image and reading a file:
+
 ```rust
-use nod::disc::{new_disc_base, PartHeader};
-use nod::fst::NodeType;
-use nod::io::new_disc_io;
 use std::io::Read;
 
-let mut disc_io = new_disc_io("path/to/file".as_ref())?;
+use nod::{
-let disc_base = new_disc_base(disc_io.as_mut())?;
+    disc::{new_disc_base, PartHeader},
-let mut partition = disc_base.get_data_partition(disc_io.as_mut())?;
+    fst::NodeType,
-let header = partition.read_header()?;
+    io::{new_disc_io, DiscIOOptions},
-if let Some(NodeType::File(node)) = header.find_node("/MP3/Worlds.txt") {
+};
-    let mut s = String::new();
+
-    partition.begin_file_stream(node)?.read_to_string(&mut s);
+fn main() -> nod::Result<()> {
-    println!(s);
+    let options = DiscIOOptions::default();
+    let mut disc_io = new_disc_io("path/to/file.iso".as_ref(), &options)?;
+    let disc_base = new_disc_base(disc_io.as_mut())?;
+    let mut partition = disc_base.get_data_partition(disc_io.as_mut(), false)?;
+    let header = partition.read_header()?;
+    if let Some(NodeType::File(node)) = header.find_node("/MP3/Worlds.txt") {
+        let mut s = String::new();
+        partition.begin_file_stream(node)?.read_to_string(&mut s).expect("Failed to read file");
+        println!("{}", s);
+    }
+    Ok(())
 }
 ```
 

rustfmt.toml

@@ -6,3 +6,4 @@ reorder_impl_items = true
 use_field_init_shorthand = true
 use_small_heuristics = "Max"
 where_single_line = true
+format_code_in_doc_comments = true

src/bin.rs

@@ -1,74 +1,205 @@
 use std::{
-    env, fs, io,
+    error::Error,
-    io::BufWriter,
+    fs,
+    fs::File,
+    io,
+    io::{BufWriter, Write},
     path::{Path, PathBuf},
 };
 
-use clap::{clap_app, AppSettings};
+use argh_derive::FromArgs;
 use nod::{
-    disc::{new_disc_base, PartReadStream},
+    disc::{new_disc_base, PartHeader, PartReadStream, PartitionType},
     fst::NodeType,
-    io::{has_extension, new_disc_io},
+    io::{has_extension, new_disc_io, DiscIOOptions},
-    Result,
+    Result, ResultContext,
 };
+use sha1::Digest;
 
-fn main() -> Result<()> {
+#[derive(FromArgs, Debug)]
-    let matches = clap_app!(nodtool =>
+/// Tool for reading GameCube and Wii disc images.
-        (settings: &[
+struct TopLevel {
-            AppSettings::SubcommandRequiredElseHelp,
+    #[argh(subcommand)]
-            AppSettings::GlobalVersion,
+    command: SubCommand,
-            AppSettings::DeriveDisplayOrder,
+}
-            AppSettings::VersionlessSubcommands,
-        ])
-        (global_settings: &[
-            AppSettings::ColoredHelp,
-            AppSettings::UnifiedHelpMessage,
-        ])
-        (version: env!("CARGO_PKG_VERSION"))
-        (author: "Luke Street <luke@street.dev>")
-        (about: "Tool for reading GameCube and Wii disc images.")
-        (long_about: "Tool for reading GameCube and Wii disc images.
 
-Based on <https://github.com/AxioDL/nod>, original authors:
+#[derive(FromArgs, Debug)]
-Jack Andersen (jackoalan)
+#[argh(subcommand)]
-Phillip Stephens (Antidote)")
+enum SubCommand {
-        (@subcommand extract =>
+    Extract(ExtractArgs),
-            (about: "Extract GameCube & Wii disc images")
+    Convert(ConvertArgs),
-            (@arg FILE: +required "Path to disc image (ISO or NFS)")
+    Verify(VerifyArgs),
-            (@arg DIR: "Output directory (optional)")
+}
-            (@arg quiet: -q "Quiet output")
+
-            (@arg validate: -h "Validate disc hashes (Wii only)")
+#[derive(FromArgs, Debug)]
-        )
+/// Extract a disc image.
-    )
+#[argh(subcommand, name = "extract")]
-    .get_matches();
+struct ExtractArgs {
-    if let Some(matches) = matches.subcommand_matches("extract") {
+    #[argh(positional)]
-        let file: PathBuf = PathBuf::from(matches.value_of("FILE").unwrap());
+    /// path to disc image (ISO or NFS)
-        let output_dir: PathBuf;
+    file: PathBuf,
-        if let Some(dir) = matches.value_of("DIR") {
+    #[argh(positional)]
-            output_dir = PathBuf::from(dir);
+    /// output directory (optional)
-        } else if has_extension(file.as_path(), "nfs") {
+    out: Option<PathBuf>,
-            // Special logic to extract from content/hif_*.nfs to extracted/..
+    #[argh(switch, short = 'q')]
-            if let Some(parent) = file.parent() {
+    /// quiet output
-                output_dir = parent.with_file_name("extracted");
+    quiet: bool,
-            } else {
+    #[argh(switch, short = 'h')]
-                output_dir = file.with_extension("");
+    /// validate disc hashes (Wii only)
-            }
+    validate: bool,
-        } else {
+}
-            output_dir = file.with_extension("");
+
+#[derive(FromArgs, Debug)]
+/// Extract a disc image.
+#[argh(subcommand, name = "convert")]
+struct ConvertArgs {
+    #[argh(positional)]
+    /// path to disc image
+    file: PathBuf,
+    #[argh(positional)]
+    /// output ISO file
+    out: PathBuf,
+}
+
+#[derive(FromArgs, Debug)]
+/// Verifies a disc image.
+#[argh(subcommand, name = "verify")]
+struct VerifyArgs {
+    #[argh(positional)]
+    /// path to disc image
+    file: PathBuf,
+}
+
+fn main() {
+    let args: TopLevel = argh::from_env();
+    let result = match args.command {
+        SubCommand::Convert(c_args) => convert(c_args),
+        SubCommand::Extract(c_args) => extract(c_args),
+        SubCommand::Verify(c_args) => verify(c_args),
+    };
+    if let Err(e) = result {
+        eprintln!("Failed: {}", e);
+        if let Some(source) = e.source() {
+            eprintln!("Caused by: {}", source);
         }
-        let mut disc_io = new_disc_io(file.as_path())?;
+        std::process::exit(1);
-        let disc_base = new_disc_base(disc_io.as_mut())?;
-        let mut partition =
-            disc_base.get_data_partition(disc_io.as_mut(), matches.is_present("validate"))?;
-        let header = partition.read_header()?;
-        extract_node(
-            header.root_node(),
-            partition.as_mut(),
-            output_dir.as_path(),
-            matches.is_present("quiet"),
-        )?;
     }
-    Result::Ok(())
+}
+
+fn convert(args: ConvertArgs) -> Result<()> { convert_and_verify(&args.file, Some(&args.out)) }
+
+fn verify(args: VerifyArgs) -> Result<()> { convert_and_verify(&args.file, None) }
+
+fn convert_and_verify(in_file: &Path, out_file: Option<&Path>) -> Result<()> {
+    println!("Loading {}", in_file.display());
+    let mut disc_io = new_disc_io(in_file, &DiscIOOptions { rebuild_hashes: true })?;
+    let disc_base = new_disc_base(disc_io.as_mut())?;
+    let header = disc_base.get_header();
+    println!(
+        "\nGame ID: {}{}{}{}{}{}",
+        header.game_id[0] as char,
+        header.game_id[1] as char,
+        header.game_id[2] as char,
+        header.game_id[3] as char,
+        header.game_id[4] as char,
+        header.game_id[5] as char
+    );
+    println!("Game title: {}", header.game_title);
+    println!("Disc num: {}", header.disc_num);
+    println!("Disc version: {}", header.disc_version);
+
+    let mut stream = disc_io.begin_read_stream(0).context("Creating disc read stream")?;
+    let mut crc = crc32fast::Hasher::new();
+    let mut md5 = md5::Md5::new();
+    let mut sha1 = sha1::Sha1::new();
+
+    let mut file = if let Some(out_file) = out_file {
+        Some(
+            File::create(out_file)
+                .with_context(|| format!("Creating file {}", out_file.display()))?,
+        )
+    } else {
+        None
+    };
+
+    const BUFFER_SIZE: usize = 1015808; // LCM(0x8000, 0x7C00)
+    let mut buf = vec![0u8; BUFFER_SIZE];
+    let mut total_read = 0u64;
+    loop {
+        let read = stream.read(&mut buf).with_context(|| {
+            format!("Reading {} bytes at disc offset {}", BUFFER_SIZE, total_read)
+        })?;
+        if read == 0 {
+            break;
+        }
+        let slice = &buf[..read];
+        crc.update(slice);
+        md5.update(slice);
+        sha1.update(slice);
+        if let Some(file) = &mut file {
+            file.write_all(slice).with_context(|| {
+                format!("Writing {} bytes at offset {}", slice.len(), total_read)
+            })?;
+        }
+        total_read += read as u64;
+    }
+
+    println!();
+    println!("CRC32: {:08x}", crc.finalize());
+    println!("MD5:   {:032x}", md5.finalize());
+    println!("SHA-1: {:040x}", sha1.finalize());
+    if let (Some(path), Some(file)) = (out_file, &mut file) {
+        file.flush().context("Flushing output file")?;
+        println!("Wrote {} to {}", file_size::fit_4(total_read), path.display());
+    }
+    Ok(())
+}
+
+fn extract(args: ExtractArgs) -> Result<()> {
+    let output_dir: PathBuf;
+    if let Some(dir) = args.out {
+        output_dir = dir;
+    } else if has_extension(&args.file, "nfs") {
+        // Special logic to extract from content/hif_*.nfs to extracted/..
+        if let Some(parent) = args.file.parent() {
+            output_dir = parent.with_file_name("extracted");
+        } else {
+            output_dir = args.file.with_extension("");
+        }
+    } else {
+        output_dir = args.file.with_extension("");
+    }
+    let mut disc_io = new_disc_io(&args.file, &DiscIOOptions { rebuild_hashes: args.validate })?;
+    let disc_base = new_disc_base(disc_io.as_mut())?;
+    let mut partition =
+        disc_base.get_partition(disc_io.as_mut(), PartitionType::Data, args.validate)?;
+    let header = partition.read_header()?;
+    extract_sys_files(header.as_ref(), &output_dir.join("sys"), args.quiet)?;
+    extract_node(header.root_node(), partition.as_mut(), &output_dir.join("files"), args.quiet)?;
+    Ok(())
+}
+
+fn extract_sys_files(header: &dyn PartHeader, out_dir: &Path, quiet: bool) -> Result<()> {
+    fs::create_dir_all(out_dir)
+        .with_context(|| format!("Creating output directory {}", out_dir.display()))?;
+    extract_file(header.boot_bytes(), &out_dir.join("boot.bin"), quiet)?;
+    extract_file(header.bi2_bytes(), &out_dir.join("bi2.bin"), quiet)?;
+    extract_file(header.apploader_bytes(), &out_dir.join("apploader.img"), quiet)?;
+    extract_file(header.fst_bytes(), &out_dir.join("fst.bin"), quiet)?;
+    extract_file(header.dol_bytes(), &out_dir.join("main.dol"), quiet)?;
+    Ok(())
+}
+
+fn extract_file(bytes: &[u8], out_path: &Path, quiet: bool) -> Result<()> {
+    if !quiet {
+        println!(
+            "Extracting {} (size: {})",
+            out_path.display(),
+            file_size::fit_4(bytes.len() as u64)
+        );
+    }
+    fs::write(out_path, bytes).with_context(|| format!("Writing file {}", out_path.display()))?;
+    Ok(())
 }
 
 fn extract_node(
@@ -76,37 +207,49 @@ fn extract_node(
     partition: &mut dyn PartReadStream,
     base_path: &Path,
     quiet: bool,
-) -> io::Result<()> {
+) -> Result<()> {
     match node {
         NodeType::File(v) => {
-            let mut file_path = base_path.to_owned();
+            let mut file_path = base_path.to_path_buf();
-            file_path.push(v.name.as_ref());
+            file_path.push(v.name.as_str());
             if !quiet {
                 println!(
                     "Extracting {} (size: {})",
-                    file_path.to_string_lossy(),
+                    file_path.display(),
                     file_size::fit_4(v.length as u64)
                 );
             }
-            let file = fs::File::create(file_path)?;
+            let file = File::create(&file_path)
+                .with_context(|| format!("Creating file {}", file_path.display()))?;
             let mut buf_writer = BufWriter::with_capacity(partition.ideal_buffer_size(), file);
-            io::copy(&mut partition.begin_file_stream(v)?, &mut buf_writer)?;
+            let mut stream = partition.begin_file_stream(v).with_context(|| {
+                format!(
+                    "Opening file {} on disc for reading (offset {}, size {})",
+                    v.name, v.offset, v.length
+                )
+            })?;
+            io::copy(&mut stream, &mut buf_writer)
+                .with_context(|| format!("Extracting file {}", file_path.display()))?;
+            buf_writer.flush().with_context(|| format!("Flushing file {}", file_path.display()))?;
         }
         NodeType::Directory(v, c) => {
             if v.name.is_empty() {
-                fs::create_dir_all(base_path)?;
+                fs::create_dir_all(base_path).with_context(|| {
+                    format!("Creating output directory {}", base_path.display())
+                })?;
                 for x in c {
                     extract_node(x, partition, base_path, quiet)?;
                 }
             } else {
-                let mut new_base = base_path.to_owned();
+                let mut new_base = base_path.to_path_buf();
-                new_base.push(v.name.as_ref());
+                new_base.push(v.name.as_str());
-                fs::create_dir_all(&new_base)?;
+                fs::create_dir_all(&new_base)
+                    .with_context(|| format!("Creating output directory {}", new_base.display()))?;
                 for x in c {
                     extract_node(x, partition, new_base.as_path(), quiet)?;
                 }
             }
         }
     }
-    io::Result::Ok(())
+    Ok(())
 }

src/disc/gcn.rs

@@ -1,16 +1,20 @@
 use std::{
     io,
-    io::{Read, Seek, SeekFrom},
+    io::{Cursor, Read, Seek, SeekFrom},
 };
 
-use binrw::{BinRead, BinReaderExt};
-
 use crate::{
-    disc::{BI2Header, DiscBase, DiscIO, Header, PartHeader, PartReadStream, BUFFER_SIZE},
+    disc::{
-    div_rem,
+        AppLoaderHeader, DiscBase, DiscIO, DolHeader, Header, PartHeader, PartReadStream,
-    fst::{find_node, node_parser, Node, NodeKind, NodeType},
+        PartitionHeader, PartitionType, SECTOR_SIZE,
+    },
+    fst::{find_node, read_fst, Node, NodeKind, NodeType},
     streams::{ReadStream, SharedWindowedReadStream},
-    Result,
+    util::{
+        div_rem,
+        reader::{read_bytes, FromReader},
+    },
+    Error, Result, ResultContext,
 };
 
 pub(crate) struct DiscGCN {
@@ -18,7 +22,7 @@ pub(crate) struct DiscGCN {
 }
 
 impl DiscGCN {
-    pub(crate) fn new(header: Header) -> Result<DiscGCN> { Result::Ok(DiscGCN { header }) }
+    pub(crate) fn new(header: Header) -> Result<DiscGCN> { Ok(DiscGCN { header }) }
 }
 
 impl DiscBase for DiscGCN {
@@ -29,37 +33,62 @@ impl DiscBase for DiscGCN {
         disc_io: &'a mut dyn DiscIO,
         _validate_hashes: bool,
     ) -> Result<Box<dyn PartReadStream + 'a>> {
-        Result::Ok(Box::from(GCPartReadStream {
+        let stream = disc_io.begin_read_stream(0).context("Opening data partition stream")?;
-            stream: disc_io.begin_read_stream(0)?,
+        Ok(Box::from(GCPartReadStream {
+            stream,
             offset: 0,
-            cur_block: u64::MAX,
+            cur_block: u32::MAX,
-            buf: [0; BUFFER_SIZE],
+            buf: [0; SECTOR_SIZE],
         }))
     }
+
+    fn get_partition<'a>(
+        &self,
+        disc_io: &'a mut dyn DiscIO,
+        part_type: PartitionType,
+        _validate_hashes: bool,
+    ) -> Result<Box<dyn PartReadStream + 'a>> {
+        if part_type == PartitionType::Data {
+            Ok(Box::from(GCPartReadStream {
+                stream: disc_io.begin_read_stream(0).context("Opening partition read stream")?,
+                offset: 0,
+                cur_block: u32::MAX,
+                buf: [0; SECTOR_SIZE],
+            }))
+        } else {
+            Err(Error::DiscFormat(format!(
+                "Invalid partition type {:?} for GameCube disc",
+                part_type
+            )))
+        }
+    }
 }
 
 struct GCPartReadStream<'a> {
     stream: Box<dyn ReadStream + 'a>,
     offset: u64,
-    cur_block: u64,
+    cur_block: u32,
-    buf: [u8; BUFFER_SIZE],
+    buf: [u8; SECTOR_SIZE],
 }
 
 impl<'a> Read for GCPartReadStream<'a> {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
-        let (mut block, mut block_offset) = div_rem(self.offset as usize, BUFFER_SIZE);
+        let (block, block_offset) = div_rem(self.offset, SECTOR_SIZE as u64);
+        let mut block = block as u32;
+        let mut block_offset = block_offset as usize;
+
         let mut rem = buf.len();
         let mut read: usize = 0;
 
         while rem > 0 {
-            if block != self.cur_block as usize {
+            if block != self.cur_block {
                 self.stream.read_exact(&mut self.buf)?;
-                self.cur_block = block as u64;
+                self.cur_block = block;
             }
 
             let mut cache_size = rem;
-            if cache_size + block_offset > BUFFER_SIZE {
+            if cache_size + block_offset > SECTOR_SIZE {
-                cache_size = BUFFER_SIZE - block_offset;
+                cache_size = SECTOR_SIZE - block_offset;
             }
 
             buf[read..read + cache_size]
@@ -71,7 +100,7 @@ impl<'a> Read for GCPartReadStream<'a> {
         }
 
         self.offset += buf.len() as u64;
-        io::Result::Ok(buf.len())
+        Ok(buf.len())
     }
 }
 
@@ -82,15 +111,15 @@ impl<'a> Seek for GCPartReadStream<'a> {
             SeekFrom::End(v) => (self.stable_stream_len()? as i64 + v) as u64,
             SeekFrom::Current(v) => (self.offset as i64 + v) as u64,
         };
-        let block = self.offset / BUFFER_SIZE as u64;
+        let block = self.offset / SECTOR_SIZE as u64;
-        if block != self.cur_block {
+        if block as u32 != self.cur_block {
-            self.stream.seek(SeekFrom::Start(block * BUFFER_SIZE as u64))?;
+            self.stream.seek(SeekFrom::Start(block * SECTOR_SIZE as u64))?;
-            self.cur_block = u64::MAX;
+            self.cur_block = u32::MAX;
         }
-        io::Result::Ok(self.offset)
+        Ok(self.offset)
     }
 
-    fn stream_position(&mut self) -> io::Result<u64> { io::Result::Ok(self.offset) }
+    fn stream_position(&mut self) -> io::Result<u64> { Ok(self.offset) }
 }
 
 impl<'a> ReadStream for GCPartReadStream<'a> {
@@ -102,28 +131,129 @@ impl<'a> ReadStream for GCPartReadStream<'a> {
 impl<'a> PartReadStream for GCPartReadStream<'a> {
     fn begin_file_stream(&mut self, node: &Node) -> io::Result<SharedWindowedReadStream> {
         assert_eq!(node.kind, NodeKind::File);
-        io::Result::Ok(self.new_window(node.offset as u64, node.length as u64)?)
+        self.new_window(node.offset as u64, node.length as u64)
     }
 
     fn read_header(&mut self) -> Result<Box<dyn PartHeader>> {
-        self.seek(SeekFrom::Start(0))?;
+        self.seek(SeekFrom::Start(0)).context("Seeking to partition header")?;
-        Result::Ok(Box::from(self.read_be::<GCPartition>()?))
+        Ok(Box::from(read_part_header(self)?))
     }
 
-    fn ideal_buffer_size(&self) -> usize { BUFFER_SIZE }
+    fn ideal_buffer_size(&self) -> usize { SECTOR_SIZE }
 }
 
-#[derive(Clone, Debug, PartialEq, BinRead)]
+const BOOT_SIZE: usize = Header::STATIC_SIZE + PartitionHeader::STATIC_SIZE;
+const BI2_SIZE: usize = 0x2000;
+
+#[derive(Clone, Debug)]
 pub(crate) struct GCPartition {
+    raw_boot: [u8; BOOT_SIZE],
+    raw_bi2: [u8; BI2_SIZE],
+    raw_apploader: Vec<u8>,
+    raw_fst: Vec<u8>,
+    raw_dol: Vec<u8>,
+    // Parsed
     header: Header,
-    bi2_header: BI2Header,
+    partition_header: PartitionHeader,
-    #[br(seek_before = SeekFrom::Start(header.fst_off as u64))]
+    apploader_header: AppLoaderHeader,
-    #[br(parse_with = node_parser)]
     root_node: NodeType,
+    dol_header: DolHeader,
+}
+
+fn read_part_header<R>(reader: &mut R) -> Result<GCPartition>
+where R: Read + Seek + ?Sized {
+    // boot.bin
+    let raw_boot = <[u8; BOOT_SIZE]>::from_reader(reader).context("Reading boot.bin")?;
+    let mut boot_bytes = raw_boot.as_slice();
+    let header = Header::from_reader(&mut boot_bytes).context("Parsing disc header")?;
+    let partition_header =
+        PartitionHeader::from_reader(&mut boot_bytes).context("Parsing partition header")?;
+    debug_assert_eq!(boot_bytes.len(), 0, "failed to consume boot.bin");
+
+    // bi2.bin
+    let raw_bi2 = <[u8; BI2_SIZE]>::from_reader(reader).context("Reading bi2.bin")?;
+
+    // apploader.bin
+    let mut raw_apploader =
+        read_bytes(reader, AppLoaderHeader::STATIC_SIZE).context("Reading apploader header")?;
+    let apploader_header = AppLoaderHeader::from_reader(&mut raw_apploader.as_slice())
+        .context("Parsing apploader header")?;
+    raw_apploader.resize(
+        AppLoaderHeader::STATIC_SIZE
+            + apploader_header.size as usize
+            + apploader_header.trailer_size as usize,
+        0,
+    );
+    reader
+        .read_exact(&mut raw_apploader[AppLoaderHeader::STATIC_SIZE..])
+        .context("Reading apploader")?;
+
+    // fst.bin
+    reader
+        .seek(SeekFrom::Start(partition_header.fst_off as u64))
+        .context("Seeking to FST offset")?;
+    let raw_fst = read_bytes(reader, partition_header.fst_sz as usize).with_context(|| {
+        format!(
+            "Reading partition FST (offset {}, size {})",
+            partition_header.fst_off, partition_header.fst_sz
+        )
+    })?;
+    let root_node = read_fst(&mut Cursor::new(&*raw_fst))?;
+
+    // main.dol
+    reader
+        .seek(SeekFrom::Start(partition_header.dol_off as u64))
+        .context("Seeking to DOL offset")?;
+    let mut raw_dol = read_bytes(reader, DolHeader::STATIC_SIZE).context("Reading DOL header")?;
+    let dol_header =
+        DolHeader::from_reader(&mut raw_dol.as_slice()).context("Parsing DOL header")?;
+    let dol_size = dol_header
+        .text_offs
+        .iter()
+        .zip(&dol_header.text_sizes)
+        .map(|(offs, size)| offs + size)
+        .chain(
+            dol_header.data_offs.iter().zip(&dol_header.data_sizes).map(|(offs, size)| offs + size),
+        )
+        .max()
+        .unwrap_or(DolHeader::STATIC_SIZE as u32);
+    raw_dol.resize(dol_size as usize, 0);
+    reader.read_exact(&mut raw_dol[DolHeader::STATIC_SIZE..]).context("Reading DOL")?;
+
+    Ok(GCPartition {
+        raw_boot,
+        raw_bi2,
+        raw_apploader,
+        raw_fst,
+        raw_dol,
+        header,
+        partition_header,
+        apploader_header,
+        root_node,
+        dol_header,
+    })
 }
 
 impl PartHeader for GCPartition {
     fn root_node(&self) -> &NodeType { &self.root_node }
 
     fn find_node(&self, path: &str) -> Option<&NodeType> { find_node(&self.root_node, path) }
+
+    fn boot_bytes(&self) -> &[u8] { &self.raw_boot }
+
+    fn bi2_bytes(&self) -> &[u8] { &self.raw_bi2 }
+
+    fn apploader_bytes(&self) -> &[u8] { &self.raw_apploader }
+
+    fn fst_bytes(&self) -> &[u8] { &self.raw_fst }
+
+    fn dol_bytes(&self) -> &[u8] { &self.raw_dol }
+
+    fn disc_header(&self) -> &Header { &self.header }
+
+    fn partition_header(&self) -> &PartitionHeader { &self.partition_header }
+
+    fn apploader_header(&self) -> &AppLoaderHeader { &self.apploader_header }
+
+    fn dol_header(&self) -> &DolHeader { &self.dol_header }
 }

src/disc/mod.rs

@@ -1,22 +1,21 @@
 //! Disc type related logic (GameCube, Wii)
 
-use std::{fmt::Debug, io};
+use std::{ffi::CStr, fmt::Debug, io, io::Read};
-
-use binrw::{BinRead, BinReaderExt, NullString};
 
 use crate::{
     disc::{gcn::DiscGCN, wii::DiscWii},
     fst::{Node, NodeType},
     io::DiscIO,
     streams::{ReadStream, SharedWindowedReadStream},
-    Error, Result,
+    util::reader::{skip_bytes, struct_size, FromReader},
+    Error, Result, ResultContext,
 };
 
 pub(crate) mod gcn;
 pub(crate) mod wii;
 
 /// Shared GameCube & Wii disc header
-#[derive(Clone, Debug, PartialEq, BinRead)]
+#[derive(Clone, Debug, PartialEq)]
 pub struct Header {
     /// Game ID (e.g. GM8E01 for Metroid Prime)
     pub game_id: [u8; 6],
@@ -28,24 +27,67 @@ pub struct Header {
     pub audio_streaming: u8,
     /// Audio streaming buffer size
     pub audio_stream_buf_size: u8,
-    #[br(pad_before(14))]
     /// If this is a Wii disc, this will be 0x5D1C9EA3
     pub wii_magic: u32,
     /// If this is a GameCube disc, this will be 0xC2339F3D
     pub gcn_magic: u32,
     /// Game title
-    #[br(pad_size_to(64), map = NullString::into_string)]
     pub game_title: String,
     /// Disable hash verification
     pub disable_hash_verification: u8,
     /// Disable disc encryption and H3 hash table loading and verification
     pub disable_disc_enc: u8,
+}
+
+fn from_c_str(bytes: &[u8]) -> io::Result<String> {
+    CStr::from_bytes_until_nul(bytes)
+        .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?
+        .to_str()
+        .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
+        .map(|s| s.to_string())
+}
+
+impl FromReader for Header {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = 0x400;
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        let game_id = <[u8; 6]>::from_reader(reader)?;
+        let disc_num = u8::from_reader(reader)?;
+        let disc_version = u8::from_reader(reader)?;
+        let audio_streaming = u8::from_reader(reader)?;
+        let audio_stream_buf_size = u8::from_reader(reader)?;
+        skip_bytes::<14, _>(reader)?; // padding
+        let wii_magic = u32::from_reader(reader)?;
+        let gcn_magic = u32::from_reader(reader)?;
+        let game_title = from_c_str(&<[u8; 64]>::from_reader(reader)?)?;
+        let disable_hash_verification = u8::from_reader(reader)?;
+        let disable_disc_enc = u8::from_reader(reader)?;
+        skip_bytes::<926, _>(reader)?; // padding
+        Ok(Self {
+            game_id,
+            disc_num,
+            disc_version,
+            audio_streaming,
+            audio_stream_buf_size,
+            wii_magic,
+            gcn_magic,
+            game_title,
+            disable_hash_verification,
+            disable_disc_enc,
+        })
+    }
+}
+
+/// Partition header
+#[derive(Clone, Debug, PartialEq)]
+pub struct PartitionHeader {
     /// Debug monitor offset
-    #[br(pad_before(0x39e))]
     pub debug_mon_off: u32,
     /// Debug monitor load address
     pub debug_load_addr: u32,
-    #[br(pad_before(0x18))]
     /// Offset to main DOL (Wii: >> 2)
     pub dol_off: u32,
     /// Offset to file system table (Wii: >> 2)
@@ -59,28 +101,130 @@ pub struct Header {
     /// User position
     pub user_position: u32,
     /// User size
-    #[br(pad_after(4))]
     pub user_sz: u32,
 }
 
-#[derive(Debug, PartialEq, BinRead, Copy, Clone)]
+impl FromReader for PartitionHeader {
-pub(crate) struct BI2Header {
+    type Args<'a> = ();
-    pub(crate) debug_monitor_size: i32,
+
-    pub(crate) sim_mem_size: i32,
+    const STATIC_SIZE: usize = struct_size([
-    pub(crate) arg_offset: u32,
+        u32::STATIC_SIZE, // debug_mon_off
-    pub(crate) debug_flag: u32,
+        u32::STATIC_SIZE, // debug_load_addr
-    pub(crate) trk_address: u32,
+        0x18,             // padding
-    pub(crate) trk_size: u32,
+        u32::STATIC_SIZE, // dol_off
-    pub(crate) country_code: u32,
+        u32::STATIC_SIZE, // fst_off
-    pub(crate) unk1: u32,
+        u32::STATIC_SIZE, // fst_sz
-    pub(crate) unk2: u32,
+        u32::STATIC_SIZE, // fst_max_sz
-    pub(crate) unk3: u32,
+        u32::STATIC_SIZE, // fst_memory_address
-    pub(crate) dol_limit: u32,
+        u32::STATIC_SIZE, // user_position
-    #[br(pad_after(0x1fd0))]
+        u32::STATIC_SIZE, // user_sz
-    pub(crate) unk4: u32,
+        4,                // padding
+    ]);
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        let debug_mon_off = u32::from_reader(reader)?;
+        let debug_load_addr = u32::from_reader(reader)?;
+        skip_bytes::<0x18, _>(reader)?; // padding
+        let dol_off = u32::from_reader(reader)?;
+        let fst_off = u32::from_reader(reader)?;
+        let fst_sz = u32::from_reader(reader)?;
+        let fst_max_sz = u32::from_reader(reader)?;
+        let fst_memory_address = u32::from_reader(reader)?;
+        let user_position = u32::from_reader(reader)?;
+        let user_sz = u32::from_reader(reader)?;
+        skip_bytes::<4, _>(reader)?; // padding
+        Ok(Self {
+            debug_mon_off,
+            debug_load_addr,
+            dol_off,
+            fst_off,
+            fst_sz,
+            fst_max_sz,
+            fst_memory_address,
+            user_position,
+            user_sz,
+        })
+    }
 }
 
-pub(crate) const BUFFER_SIZE: usize = 0x8000;
+#[derive(Debug, PartialEq, Clone)]
+pub struct AppLoaderHeader {
+    pub date: String,
+    pub entry_point: u32,
+    pub size: u32,
+    pub trailer_size: u32,
+}
+
+impl FromReader for AppLoaderHeader {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = struct_size([
+        16,               // date
+        u32::STATIC_SIZE, // entry_point
+        u32::STATIC_SIZE, // size
+        u32::STATIC_SIZE, // trailer_size
+        4,                // padding
+    ]);
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        let date = from_c_str(&<[u8; 16]>::from_reader(reader)?)?;
+        let entry_point = u32::from_reader(reader)?;
+        let size = u32::from_reader(reader)?;
+        let trailer_size = u32::from_reader(reader)?;
+        skip_bytes::<4, _>(reader)?; // padding
+        Ok(Self { date, entry_point, size, trailer_size })
+    }
+}
+
+pub const DOL_MAX_TEXT_SECTIONS: usize = 7;
+pub const DOL_MAX_DATA_SECTIONS: usize = 11;
+
+#[derive(Debug, Clone)]
+pub struct DolHeader {
+    pub text_offs: [u32; DOL_MAX_TEXT_SECTIONS],
+    pub data_offs: [u32; DOL_MAX_DATA_SECTIONS],
+    pub text_addrs: [u32; DOL_MAX_TEXT_SECTIONS],
+    pub data_addrs: [u32; DOL_MAX_DATA_SECTIONS],
+    pub text_sizes: [u32; DOL_MAX_TEXT_SECTIONS],
+    pub data_sizes: [u32; DOL_MAX_DATA_SECTIONS],
+    pub bss_addr: u32,
+    pub bss_size: u32,
+    pub entry_point: u32,
+}
+
+impl FromReader for DolHeader {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = 0x100;
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        let result = Self {
+            text_offs: <_>::from_reader(reader)?,
+            data_offs: <_>::from_reader(reader)?,
+            text_addrs: <_>::from_reader(reader)?,
+            data_addrs: <_>::from_reader(reader)?,
+            text_sizes: <_>::from_reader(reader)?,
+            data_sizes: <_>::from_reader(reader)?,
+            bss_addr: <_>::from_reader(reader)?,
+            bss_size: <_>::from_reader(reader)?,
+            entry_point: <_>::from_reader(reader)?,
+        };
+        skip_bytes::<0x1C, _>(reader)?; // padding
+        Ok(result)
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Copy, Clone)]
+pub enum PartitionType {
+    Data,
+    Update,
+    Channel,
+}
+
+pub(crate) const SECTOR_SIZE: usize = 0x8000;
 
 /// Contains a disc's header & partition information.
 pub trait DiscBase: Send + Sync {
@@ -95,19 +239,35 @@ pub trait DiscBase: Send + Sync {
     ///
     /// Basic usage:
     /// ```no_run
-    /// use nod::disc::new_disc_base;
+    /// use nod::{
-    /// use nod::io::new_disc_io;
+    ///     disc::new_disc_base,
+    ///     io::{new_disc_io, DiscIOOptions},
+    /// };
     ///
-    /// let mut disc_io = new_disc_io("path/to/file".as_ref())?;
+    /// # fn main() -> nod::Result<()> {
+    /// let options = DiscIOOptions::default();
+    /// let mut disc_io = new_disc_io("path/to/file.iso".as_ref(), &options)?;
     /// let disc_base = new_disc_base(disc_io.as_mut())?;
     /// let mut partition = disc_base.get_data_partition(disc_io.as_mut(), false)?;
-    /// # Ok::<(), nod::Error>(())
+    /// # Ok(())
+    /// # }
     /// ```
     fn get_data_partition<'a>(
         &self,
         disc_io: &'a mut dyn DiscIO,
         validate_hashes: bool,
     ) -> Result<Box<dyn PartReadStream + 'a>>;
+
+    /// Opens a new partition read stream for the first partition matching
+    /// the specified type.
+    ///
+    /// `validate_hashes`: Validate Wii disc hashes while reading (slow!)
+    fn get_partition<'a>(
+        &self,
+        disc_io: &'a mut dyn DiscIO,
+        part_type: PartitionType,
+        validate_hashes: bool,
+    ) -> Result<Box<dyn PartReadStream + 'a>>;
 }
 
 /// Creates a new [`DiscBase`] instance.
@@ -116,23 +276,31 @@ pub trait DiscBase: Send + Sync {
 ///
 /// Basic usage:
 /// ```no_run
-/// use nod::io::new_disc_io;
+/// use nod::{
-/// use nod::disc::new_disc_base;
+///     disc::new_disc_base,
+///     io::{new_disc_io, DiscIOOptions},
+/// };
 ///
-/// let mut disc_io = new_disc_io("path/to/file".as_ref())?;
+/// # fn main() -> nod::Result<()> {
+/// let options = DiscIOOptions::default();
+/// let mut disc_io = new_disc_io("path/to/file.iso".as_ref(), &options)?;
 /// let disc_base = new_disc_base(disc_io.as_mut())?;
 /// disc_base.get_header();
-/// # Ok::<(), nod::Error>(())
+/// # Ok(())
+/// # }
 /// ```
 pub fn new_disc_base(disc_io: &mut dyn DiscIO) -> Result<Box<dyn DiscBase>> {
-    let mut stream = disc_io.begin_read_stream(0)?;
+    let mut stream = disc_io.begin_read_stream(0).context("Opening disc stream")?;
-    let header: Header = stream.read_be()?;
+    let header_bytes =
+        <[u8; Header::STATIC_SIZE]>::from_reader(&mut stream).context("Reading disc header")?;
+    let header =
+        Header::from_reader(&mut header_bytes.as_slice()).context("Parsing disc header")?;
     if header.wii_magic == 0x5D1C9EA3 {
-        Result::Ok(Box::from(DiscWii::new(stream.as_mut(), header)?))
+        Ok(Box::from(DiscWii::new(stream.as_mut(), header)?))
     } else if header.gcn_magic == 0xC2339F3D {
-        Result::Ok(Box::from(DiscGCN::new(header)?))
+        Ok(Box::from(DiscGCN::new(header)?))
     } else {
-        Result::Err(Error::DiscFormat("Invalid GC/Wii magic".to_string()))
+        Err(Error::DiscFormat(format!("Invalid GC/Wii magic: {:#010X}", header.wii_magic)))
     }
 }
 
@@ -145,21 +313,27 @@ pub trait PartReadStream: ReadStream {
     ///
     /// Basic usage:
     /// ```no_run
-    /// use nod::disc::{new_disc_base, PartHeader};
-    /// use nod::fst::NodeType;
-    /// use nod::io::new_disc_io;
     /// use std::io::Read;
     ///
-    /// let mut disc_io = new_disc_io("path/to/file".as_ref())?;
+    /// use nod::{
-    /// let disc_base = new_disc_base(disc_io.as_mut())?;
+    ///     disc::{new_disc_base, PartHeader},
-    /// let mut partition = disc_base.get_data_partition(disc_io.as_mut(), false)?;
+    ///     fst::NodeType,
-    /// let header = partition.read_header()?;
+    ///     io::{new_disc_io, DiscIOOptions},
-    /// if let Some(NodeType::File(node)) = header.find_node("/MP3/Worlds.txt") {
+    /// };
-    ///     let mut s = String::new();
+    ///
-    ///     partition.begin_file_stream(node)?.read_to_string(&mut s);
+    /// fn main() -> nod::Result<()> {
-    ///     println!("{}", s);
+    ///     let options = DiscIOOptions::default();
+    ///     let mut disc_io = new_disc_io("path/to/file.iso".as_ref(), &options)?;
+    ///     let disc_base = new_disc_base(disc_io.as_mut())?;
+    ///     let mut partition = disc_base.get_data_partition(disc_io.as_mut(), false)?;
+    ///     let header = partition.read_header()?;
+    ///     if let Some(NodeType::File(node)) = header.find_node("/MP3/Worlds.txt") {
+    ///         let mut s = String::new();
+    ///         partition.begin_file_stream(node)?.read_to_string(&mut s).expect("Failed to read file");
+    ///         println!("{}", s);
+    ///     }
+    ///     Ok(())
     /// }
-    /// # Ok::<(), nod::Error>(())
     /// ```
     fn begin_file_stream(&mut self, node: &Node) -> io::Result<SharedWindowedReadStream>;
 
@@ -183,21 +357,53 @@ pub trait PartHeader: Debug + Send + Sync {
     ///
     /// Basic usage:
     /// ```no_run
-    /// use nod::disc::{new_disc_base, PartHeader};
+    /// use nod::{
-    /// use nod::fst::NodeType;
+    ///     disc::{new_disc_base, PartHeader},
-    /// use nod::io::new_disc_io;
+    ///     fst::NodeType,
+    ///     io::{new_disc_io, DiscIOOptions},
+    /// };
     ///
-    /// let mut disc_io = new_disc_io("path/to/file".as_ref())?;
+    /// fn main() -> nod::Result<()> {
-    /// let disc_base = new_disc_base(disc_io.as_mut())?;
+    ///     let options = DiscIOOptions::default();
-    /// let mut partition = disc_base.get_data_partition(disc_io.as_mut(), false)?;
+    ///     let mut disc_io = new_disc_io("path/to/file.iso".as_ref(), &options)?;
-    /// let header = partition.read_header()?;
+    ///     let disc_base = new_disc_base(disc_io.as_mut())?;
-    /// if let Some(NodeType::File(node)) = header.find_node("/MP1/Metroid1.pak") {
+    ///     let mut partition = disc_base.get_data_partition(disc_io.as_mut(), false)?;
-    ///     println!("{}", node.name);
+    ///     let header = partition.read_header()?;
+    ///     if let Some(NodeType::File(node)) = header.find_node("/MP1/Metroid1.pak") {
+    ///         println!("{}", node.name);
+    ///     }
+    ///     if let Some(NodeType::Directory(node, children)) = header.find_node("/MP1") {
+    ///         println!("Number of files: {}", children.len());
+    ///     }
+    ///     Ok(())
     /// }
-    /// if let Some(NodeType::Directory(node, children)) = header.find_node("/MP1") {
-    ///     println!("Number of files: {}", children.len());
-    /// }
-    /// # Ok::<(), nod::Error>(())
     /// ```
     fn find_node(&self, path: &str) -> Option<&NodeType>;
+
+    /// Disc and partition header (boot.bin)
+    fn boot_bytes(&self) -> &[u8];
+
+    /// Debug and region information (bi2.bin)
+    fn bi2_bytes(&self) -> &[u8];
+
+    /// Apploader (apploader.bin)
+    fn apploader_bytes(&self) -> &[u8];
+
+    /// File system table (fst.bin)
+    fn fst_bytes(&self) -> &[u8];
+
+    /// Main binary (main.dol)
+    fn dol_bytes(&self) -> &[u8];
+
+    /// Disc header
+    fn disc_header(&self) -> &Header;
+
+    /// Partition header
+    fn partition_header(&self) -> &PartitionHeader;
+
+    /// Apploader header
+    fn apploader_header(&self) -> &AppLoaderHeader;
+
+    /// DOL header
+    fn dol_header(&self) -> &DolHeader;
 }

src/disc/wii.rs

@@ -3,24 +3,33 @@ use std::{
     io::{Read, Seek, SeekFrom},
 };
 
-use aes::{Aes128, Block, NewBlockCipher};
+use aes::{
-use binrw::{BinRead, BinReaderExt};
+    cipher::{block_padding::NoPadding, BlockDecryptMut, KeyIvInit},
-use block_modes::{block_padding::NoPadding, BlockMode, Cbc};
+    Aes128, Block,
+};
 use sha1::{digest, Digest, Sha1};
 
 use crate::{
     array_ref,
-    disc::{BI2Header, DiscBase, DiscIO, Header, PartHeader, PartReadStream, BUFFER_SIZE},
+    disc::{
-    div_rem,
+        AppLoaderHeader, DiscBase, DiscIO, DolHeader, Header, PartHeader, PartReadStream,
-    fst::{find_node, node_parser, Node, NodeKind, NodeType},
+        PartitionHeader, PartitionType, SECTOR_SIZE,
+    },
+    fst::{find_node, Node, NodeKind, NodeType},
     streams::{wrap_windowed, OwningWindowedReadStream, ReadStream, SharedWindowedReadStream},
-    Error, Result,
+    util::{
+        div_rem,
+        reader::{skip_bytes, struct_size, FromReader},
+    },
+    Error, Result, ResultContext,
 };
 
-type Aes128Cbc = Cbc<Aes128, NoPadding>;
+pub(crate) const HASHES_SIZE: usize = 0x400;
+pub(crate) const BLOCK_SIZE: usize = SECTOR_SIZE - HASHES_SIZE; // 0x7C00
+
+/// AES-128-CBC decryptor
+type Aes128Cbc = cbc::Decryptor<Aes128>;
 
-const BLOCK_SIZE: usize = 0x7c00;
-const BUFFER_OFFSET: usize = BUFFER_SIZE - BLOCK_SIZE;
 #[rustfmt::skip]
 const COMMON_KEYS: [[u8; 16]; 2] = [
     /* Normal */
@@ -29,82 +38,186 @@ const COMMON_KEYS: [[u8; 16]; 2] = [
     [0x63, 0xb8, 0x2b, 0xb4, 0xf4, 0x61, 0x4e, 0x2e, 0x13, 0xf2, 0xfe, 0xfb, 0xba, 0x4c, 0x9b, 0x7e],
 ];
 
-#[derive(Debug, PartialEq, BinRead)]
+#[derive(Debug, PartialEq, Eq, Copy, Clone)]
-#[br(repr = u32)]
-enum WiiPartType {
-    Data,
-    Update,
-    Channel,
-}
-
-#[derive(Debug, PartialEq, BinRead)]
-#[br(repr = u32)]
 enum SigType {
-    Rsa4096 = 0x00010000,
+    Rsa4096,
-    Rsa2048 = 0x00010001,
+    Rsa2048,
-    EllipticalCurve = 0x00010002,
+    EllipticalCurve,
 }
 
-#[derive(Debug, PartialEq, BinRead)]
+impl FromReader for SigType {
-#[br(repr = u32)]
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = u32::STATIC_SIZE;
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        match u32::from_reader(reader)? {
+            0x00010000 => Ok(SigType::Rsa4096),
+            0x00010001 => Ok(SigType::Rsa2048),
+            0x00010002 => Ok(SigType::EllipticalCurve),
+            _ => Err(io::Error::new(io::ErrorKind::InvalidData, "invalid signature type")),
+        }
+    }
+}
+
+impl SigType {
+    fn size(self) -> usize {
+        match self {
+            SigType::Rsa4096 => 512,
+            SigType::Rsa2048 => 256,
+            SigType::EllipticalCurve => 64,
+        }
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Copy, Clone)]
 enum KeyType {
-    Rsa4096 = 0x00000000,
+    Rsa4096,
-    Rsa2048 = 0x00000001,
+    Rsa2048,
 }
 
-#[derive(Debug, PartialEq, BinRead)]
+impl FromReader for KeyType {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = u32::STATIC_SIZE;
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        match u32::from_reader(reader)? {
+            0x00000000 => Ok(KeyType::Rsa4096),
+            0x00000001 => Ok(KeyType::Rsa2048),
+            _ => Err(io::Error::new(io::ErrorKind::InvalidData, "invalid key type")),
+        }
+    }
+}
+
+impl KeyType {
+    fn size(self) -> usize {
+        match self {
+            KeyType::Rsa4096 => 512,
+            KeyType::Rsa2048 => 256,
+        }
+    }
+}
+
+#[derive(Debug, PartialEq)]
 struct WiiPart {
-    #[br(map = | x: u32 | (x as u64) << 2)]
+    // #[br(map = |x: u32| (x as u64) << 2)]
     part_data_off: u64,
-    part_type: WiiPartType,
+    part_type: PartitionType,
-    #[br(restore_position, args(part_data_off))]
+    // #[br(restore_position, args(part_data_off))]
     part_header: WiiPartitionHeader,
 }
 
-#[derive(Debug, PartialEq, BinRead)]
+#[derive(Debug, PartialEq)]
 struct WiiPartInfo {
-    #[br(seek_before = SeekFrom::Start(0x40000))]
+    // #[br(seek_before = SeekFrom::Start(0x40000))]
     part_count: u32,
-    #[br(map = | x: u32 | (x as u64) << 2)]
+    // #[br(map = |x: u32| (x as u64) << 2)]
     part_info_off: u64,
-    #[br(seek_before = SeekFrom::Start(part_info_off), count = part_count)]
+    // #[br(seek_before = SeekFrom::Start(part_info_off), count = part_count)]
     parts: Vec<WiiPart>,
 }
 
-#[derive(Debug, PartialEq, BinRead)]
+#[derive(Debug, PartialEq, Default)]
 struct TicketTimeLimit {
     enable_time_limit: u32,
     time_limit: u32,
 }
 
-#[derive(Debug, PartialEq, BinRead)]
+impl FromReader for TicketTimeLimit {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = struct_size([
+        u32::STATIC_SIZE, // enable_time_limit
+        u32::STATIC_SIZE, // time_limit
+    ]);
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        let enable_time_limit = u32::from_reader(reader)?;
+        let time_limit = u32::from_reader(reader)?;
+        Ok(TicketTimeLimit { enable_time_limit, time_limit })
+    }
+}
+
+#[derive(Debug, PartialEq)]
 struct Ticket {
     sig_type: SigType,
-    #[br(count = 256)]
+    sig: [u8; 256],
-    sig: Vec<u8>,
+    sig_issuer: [u8; 64],
-    #[br(pad_before = 60, count = 64)]
+    ecdh: [u8; 60],
-    sig_issuer: Vec<u8>,
-    #[br(count = 60)]
-    ecdh: Vec<u8>,
-    #[br(pad_before = 3)]
     enc_key: [u8; 16],
-    #[br(pad_before = 1)]
     ticket_id: [u8; 8],
     console_id: [u8; 4],
     title_id: [u8; 8],
-    #[br(pad_before = 2)]
     ticket_version: u16,
     permitted_titles_mask: u32,
     permit_mask: u32,
     title_export_allowed: u8,
     common_key_idx: u8,
-    #[br(pad_before = 48, count = 64)]
+    content_access_permissions: [u8; 64],
-    content_access_permissions: Vec<u8>,
+    time_limits: [TicketTimeLimit; 8],
-    #[br(pad_before = 2, count = 8)]
-    time_limits: Vec<TicketTimeLimit>,
 }
 
-#[derive(Debug, PartialEq, BinRead)]
+impl FromReader for Ticket {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = 0x2A4;
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        let sig_type = SigType::from_reader(reader)?;
+        let sig = <[u8; 256]>::from_reader(reader)?;
+        skip_bytes::<0x3C, _>(reader)?;
+        let sig_issuer = <[u8; 64]>::from_reader(reader)?;
+        let ecdh = <[u8; 60]>::from_reader(reader)?;
+        skip_bytes::<3, _>(reader)?;
+        let enc_key = <[u8; 16]>::from_reader(reader)?;
+        skip_bytes::<1, _>(reader)?;
+        let ticket_id = <[u8; 8]>::from_reader(reader)?;
+        let console_id = <[u8; 4]>::from_reader(reader)?;
+        let title_id = <[u8; 8]>::from_reader(reader)?;
+        skip_bytes::<2, _>(reader)?;
+        let ticket_version = u16::from_reader(reader)?;
+        let permitted_titles_mask = u32::from_reader(reader)?;
+        let permit_mask = u32::from_reader(reader)?;
+        let title_export_allowed = u8::from_reader(reader)?;
+        let common_key_idx = u8::from_reader(reader)?;
+        skip_bytes::<48, _>(reader)?;
+        let content_access_permissions = <[u8; 64]>::from_reader(reader)?;
+        let time_limits = [
+            TicketTimeLimit::from_reader(reader)?,
+            TicketTimeLimit::from_reader(reader)?,
+            TicketTimeLimit::from_reader(reader)?,
+            TicketTimeLimit::from_reader(reader)?,
+            TicketTimeLimit::from_reader(reader)?,
+            TicketTimeLimit::from_reader(reader)?,
+            TicketTimeLimit::from_reader(reader)?,
+            TicketTimeLimit::from_reader(reader)?,
+        ];
+        Ok(Ticket {
+            sig_type,
+            sig,
+            sig_issuer,
+            ecdh,
+            enc_key,
+            ticket_id,
+            console_id,
+            title_id,
+            ticket_version,
+            permitted_titles_mask,
+            permit_mask,
+            title_export_allowed,
+            common_key_idx,
+            content_access_permissions,
+            time_limits,
+        })
+    }
+}
+
+#[derive(Debug, PartialEq)]
 struct TmdContent {
     id: u32,
     index: u16,
@@ -113,78 +226,89 @@ struct TmdContent {
     hash: [u8; 20],
 }
 
-#[derive(Debug, PartialEq, BinRead)]
+#[derive(Debug, PartialEq)]
 struct Tmd {
     sig_type: SigType,
-    #[br(count = 256)]
+    // #[br(count = 256)]
     sig: Vec<u8>,
-    #[br(pad_before = 60, count = 64)]
+    // #[br(pad_before = 60, count = 64)]
     sig_issuer: Vec<u8>,
     version: u8,
     ca_crl_version: u8,
     signer_crl_version: u8,
-    #[br(pad_before = 1)]
+    // #[br(pad_before = 1)]
     ios_id_major: u32,
     ios_id_minor: u32,
     title_id_major: u32,
-    title_id_minor: [char; 4],
+    title_id_minor: [u8; 4],
     title_type: u32,
     group_id: u16,
-    #[br(pad_before = 62)]
+    // #[br(pad_before = 62)]
     access_flags: u32,
     title_version: u16,
     num_contents: u16,
-    #[br(pad_after = 2)]
+    // #[br(pad_after = 2)]
     boot_idx: u16,
-    #[br(count = num_contents)]
+    // #[br(count = num_contents)]
     contents: Vec<TmdContent>,
 }
 
-#[derive(Debug, PartialEq, BinRead)]
+#[derive(Debug, PartialEq)]
 struct Certificate {
     sig_type: SigType,
-    #[br(count = if sig_type == SigType::Rsa4096 { 512 } else if sig_type == SigType::Rsa2048 { 256 } else if sig_type == SigType::EllipticalCurve { 64 } else { 0 })]
+    // #[br(count = sig_size(sig_type))]
     sig: Vec<u8>,
-    #[br(pad_before = 60, count = 64)]
+    // #[br(pad_before = 60, count = 64)]
     issuer: Vec<u8>,
     key_type: KeyType,
-    #[br(count = 64)]
+    // #[br(count = 64)]
     subject: Vec<u8>,
-    #[br(count = if key_type == KeyType::Rsa4096 { 512 } else if key_type == KeyType::Rsa2048 { 256 } else { 0 })]
+    // #[br(count = key_size(key_type))]
     key: Vec<u8>,
     modulus: u32,
-    #[br(pad_after = 52)]
+    // #[br(pad_after = 52)]
     pub_exp: u32,
 }
 
-#[derive(Debug, PartialEq, BinRead)]
+#[derive(Debug, PartialEq)]
-#[br(import(partition_off: u64))]
+// #[br(import(partition_off: u64))]
 struct WiiPartitionHeader {
-    #[br(seek_before = SeekFrom::Start(partition_off))]
+    // #[br(seek_before = SeekFrom::Start(partition_off))]
     ticket: Ticket,
     tmd_size: u32,
-    #[br(map = | x: u32 | ((x as u64) << 2) + partition_off)]
+    // #[br(map = |x: u32| ((x as u64) << 2) + partition_off)]
     tmd_off: u64,
     cert_chain_size: u32,
-    #[br(map = | x: u32 | ((x as u64) << 2) + partition_off)]
+    // #[br(map = |x: u32| ((x as u64) << 2) + partition_off)]
     cert_chain_off: u64,
-    #[br(map = | x: u32 | ((x as u64) << 2) + partition_off)]
+    // #[br(map = |x: u32| ((x as u64) << 2) + partition_off)]
     global_hash_table_off: u64,
-    #[br(map = | x: u32 | ((x as u64) << 2) + partition_off)]
+    // #[br(map = |x: u32| ((x as u64) << 2) + partition_off)]
     data_off: u64,
-    #[br(map = | x: u32 | (x as u64) << 2)]
+    // #[br(map = |x: u32| (x as u64) << 2)]
     data_size: u64,
 
-    #[br(seek_before = SeekFrom::Start(tmd_off))]
+    // #[br(seek_before = SeekFrom::Start(tmd_off))]
     tmd: Tmd,
-    #[br(seek_before = SeekFrom::Start(cert_chain_off))]
+    // #[br(seek_before = SeekFrom::Start(cert_chain_off))]
     ca_cert: Certificate,
     tmd_cert: Certificate,
     ticket_cert: Certificate,
-    #[br(seek_before = SeekFrom::Start(global_hash_table_off), count = 0x18000)]
+    // #[br(seek_before = SeekFrom::Start(global_hash_table_off), count = 0x18000)]
     h3_data: Vec<u8>,
 }
 
+impl FromReader for WiiPartitionHeader {
+    type Args<'a> = u64;
+
+    const STATIC_SIZE: usize = Ticket::STATIC_SIZE;
+
+    fn from_reader_args<R>(reader: &mut R, args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        todo!()
+    }
+}
+
 pub(crate) struct DiscWii {
     header: Header,
     part_info: WiiPartInfo,
@@ -192,9 +316,9 @@ pub(crate) struct DiscWii {
 
 impl DiscWii {
     pub(crate) fn new(mut stream: &mut dyn ReadStream, header: Header) -> Result<DiscWii> {
-        let mut disc = DiscWii { header, part_info: stream.read_be()? };
+        let mut disc = DiscWii { header, part_info: todo!() }; // stream.read_be()?
         disc.decrypt_partition_keys()?;
-        Result::Ok(disc)
+        Ok(disc)
     }
 }
 
@@ -204,13 +328,10 @@ impl DiscWii {
             let ticket = &mut part.part_header.ticket;
             let mut iv: [u8; 16] = [0; 16];
             iv[..8].copy_from_slice(&ticket.title_id);
-            Aes128Cbc::new(
+            Aes128Cbc::new(&COMMON_KEYS[ticket.common_key_idx as usize].into(), &iv.into())
-                Aes128::new(&COMMON_KEYS[ticket.common_key_idx as usize].into()),
+                .decrypt_padded_mut::<NoPadding>(&mut ticket.enc_key)?;
-                &iv.into(),
-            )
-            .decrypt(&mut ticket.enc_key)?;
         }
-        Result::Ok(())
+        Ok(())
     }
 }
 
@@ -226,48 +347,74 @@ impl DiscBase for DiscWii {
             .part_info
             .parts
             .iter()
-            .find(|v| v.part_type == WiiPartType::Data)
+            .find(|v| v.part_type == PartitionType::Data)
             .ok_or_else(|| Error::DiscFormat("Failed to locate data partition".to_string()))?;
         let data_off = part.part_header.data_off;
         let has_crypto = disc_io.has_wii_crypto();
+        let base = disc_io
+            .begin_read_stream(data_off)
+            .map_err(|e| Error::Io("Opening data partition stream".to_string(), e))?;
+        let stream = wrap_windowed(base, data_off, part.part_header.data_size)
+            .context("Wrapping data partition stream")?;
         let result = Box::new(WiiPartReadStream {
-            stream: wrap_windowed(
+            stream,
-                disc_io.begin_read_stream(data_off)?,
+            crypto: if has_crypto { Some(part.part_header.ticket.enc_key) } else { None },
-                data_off,
-                part.part_header.data_size,
-            )?,
-            crypto: if has_crypto {
-                Aes128::new(&part.part_header.ticket.enc_key.into()).into()
-            } else {
-                Option::None
-            },
             offset: 0,
-            cur_block: u64::MAX,
+            cur_block: u32::MAX,
             buf: [0; 0x8000],
             validate_hashes,
         });
-        Result::Ok(result)
+        Ok(result)
+    }
+
+    fn get_partition<'a>(
+        &self,
+        disc_io: &'a mut dyn DiscIO,
+        part_type: PartitionType,
+        validate_hashes: bool,
+    ) -> Result<Box<dyn PartReadStream + 'a>> {
+        let part =
+            self.part_info.parts.iter().find(|v| v.part_type == part_type).ok_or_else(|| {
+                Error::DiscFormat(format!("Failed to locate {:?} partition", part_type))
+            })?;
+        let data_off = part.part_header.data_off;
+        let has_crypto = disc_io.has_wii_crypto();
+        let base = disc_io
+            .begin_read_stream(data_off)
+            .with_context(|| format!("Opening {:?} partition stream", part_type))?;
+        let stream = wrap_windowed(base, data_off, part.part_header.data_size)
+            .with_context(|| format!("Wrapping {:?} partition stream", part_type))?;
+        let result = Box::new(WiiPartReadStream {
+            stream,
+            crypto: if has_crypto { Some(part.part_header.ticket.enc_key) } else { None },
+            offset: 0,
+            cur_block: u32::MAX,
+            buf: [0; 0x8000],
+            validate_hashes,
+        });
+        Ok(result)
     }
 }
 
 struct WiiPartReadStream<'a> {
     stream: OwningWindowedReadStream<'a>,
-    crypto: Option<Aes128>,
+    crypto: Option<[u8; 16]>,
     offset: u64,
-    cur_block: u64,
+    cur_block: u32,
-    buf: [u8; BUFFER_SIZE],
+    buf: [u8; SECTOR_SIZE],
     validate_hashes: bool,
 }
 
 impl<'a> PartReadStream for WiiPartReadStream<'a> {
     fn begin_file_stream(&mut self, node: &Node) -> io::Result<SharedWindowedReadStream> {
         assert_eq!(node.kind, NodeKind::File);
-        io::Result::Ok(self.new_window((node.offset as u64) << 2, node.length as u64)?)
+        self.new_window((node.offset as u64) << 2, node.length as u64)
     }
 
     fn read_header(&mut self) -> Result<Box<dyn PartHeader>> {
-        self.seek(SeekFrom::Start(0))?;
+        self.seek(SeekFrom::Start(0)).context("Seeking to partition header")?;
-        Result::Ok(Box::from(self.read_be::<WiiPartition>()?))
+        todo!()
+        // Ok(Box::from(self.read_be::<WiiPartition>()?))
     }
 
     fn ideal_buffer_size(&self) -> usize { BLOCK_SIZE }
@@ -276,25 +423,24 @@ impl<'a> PartReadStream for WiiPartReadStream<'a> {
 #[inline(always)]
 fn as_digest(slice: &[u8; 20]) -> digest::Output<Sha1> { (*slice).into() }
 
-fn decrypt_block(part: &mut WiiPartReadStream, cluster: usize) -> io::Result<()> {
+fn decrypt_block(part: &mut WiiPartReadStream, cluster: u32) -> io::Result<()> {
     part.stream.read_exact(&mut part.buf)?;
-    if part.crypto.is_some() {
+    if let Some(key) = &part.crypto {
         // Fetch IV before decrypting header
-        let iv = Block::from(*array_ref![part.buf, 0x3d0, 16]);
+        let iv_bytes = array_ref![part.buf, 0x3d0, 16];
+        let iv = Block::from(*iv_bytes);
         // Don't need to decrypt header if we're not validating hashes
         if part.validate_hashes {
-            Aes128Cbc::new(part.crypto.as_ref().unwrap().clone(), &Block::from([0; 16]))
+            Aes128Cbc::new(key.into(), &Block::from([0; 16]))
-                .decrypt(&mut part.buf[..BUFFER_OFFSET])
+                .decrypt_padded_mut::<NoPadding>(&mut part.buf[..HASHES_SIZE])
                 .expect("Failed to decrypt header");
         }
-        Aes128Cbc::new(part.crypto.as_ref().unwrap().clone(), &iv)
+        Aes128Cbc::new(key.into(), &iv)
-            .decrypt(&mut part.buf[BUFFER_OFFSET..])
+            .decrypt_padded_mut::<NoPadding>(&mut part.buf[HASHES_SIZE..])
             .expect("Failed to decrypt block");
     }
-    if part.validate_hashes && part.crypto.is_some()
+    if part.validate_hashes {
-    /* FIXME NFS validation? */
+        let (mut group, sub_group) = div_rem(cluster as usize, 8);
-    {
-        let (mut group, sub_group) = div_rem(cluster, 8);
         group %= 8;
         // H0 hashes
         for i in 0..31 {
@@ -303,12 +449,7 @@ fn decrypt_block(part: &mut WiiPartReadStream, cluster: usize) -> io::Result<()>
             let expected = as_digest(array_ref![part.buf, i * 20, 20]);
             let output = hash.finalize();
             if output != expected {
-                panic!(
+                panic!("Invalid H0 hash! (block {:?}) {:x}\n\texpected {:x}", i, output, expected);
-                    "Invalid hash! (block {:?}) {:?}\n\texpected {:?}",
-                    i,
-                    output.as_slice(),
-                    expected
-                );
             }
         }
         // H1 hash
@@ -319,10 +460,8 @@ fn decrypt_block(part: &mut WiiPartReadStream, cluster: usize) -> io::Result<()>
             let output = hash.finalize();
             if output != expected {
                 panic!(
-                    "Invalid hash! (subgroup {:?}) {:?}\n\texpected {:?}",
+                    "Invalid H1 hash! (subgroup {:?}) {:x}\n\texpected {:x}",
-                    sub_group,
+                    sub_group, output, expected
-                    output.as_slice(),
-                    expected
                 );
             }
         }
@@ -334,27 +473,28 @@ fn decrypt_block(part: &mut WiiPartReadStream, cluster: usize) -> io::Result<()>
             let output = hash.finalize();
             if output != expected {
                 panic!(
-                    "Invalid hash! (group {:?}) {:?}\n\texpected {:?}",
+                    "Invalid H2 hash! (group {:?}) {:x}\n\texpected {:x}",
-                    group,
+                    group, output, expected
-                    output.as_slice(),
-                    expected
                 );
             }
         }
     }
-    io::Result::Ok(())
+    Ok(())
 }
 
 impl<'a> Read for WiiPartReadStream<'a> {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
-        let (mut block, mut block_offset) = div_rem(self.offset as usize, BLOCK_SIZE);
+        let (block, block_offset) = div_rem(self.offset, BLOCK_SIZE as u64);
+        let mut block = block as u32;
+        let mut block_offset = block_offset as usize;
+
         let mut rem = buf.len();
         let mut read: usize = 0;
 
         while rem > 0 {
-            if block != self.cur_block as usize {
+            if block != self.cur_block {
                 decrypt_block(self, block)?;
-                self.cur_block = block as u64;
+                self.cur_block = block;
             }
 
             let mut cache_size = rem;
@@ -363,7 +503,7 @@ impl<'a> Read for WiiPartReadStream<'a> {
             }
 
             buf[read..read + cache_size].copy_from_slice(
-                &self.buf[BUFFER_OFFSET + block_offset..BUFFER_OFFSET + block_offset + cache_size],
+                &self.buf[HASHES_SIZE + block_offset..HASHES_SIZE + block_offset + cache_size],
             );
             read += cache_size;
             rem -= cache_size;
@@ -372,13 +512,13 @@ impl<'a> Read for WiiPartReadStream<'a> {
         }
 
         self.offset += buf.len() as u64;
-        io::Result::Ok(buf.len())
+        Ok(buf.len())
     }
 }
 
 #[inline(always)]
 fn to_block_size(v: u64) -> u64 {
-    (v / BUFFER_SIZE as u64) * BLOCK_SIZE as u64 + (v % BUFFER_SIZE as u64)
+    (v / SECTOR_SIZE as u64) * BLOCK_SIZE as u64 + (v % SECTOR_SIZE as u64)
 }
 
 impl<'a> Seek for WiiPartReadStream<'a> {
@@ -388,31 +528,33 @@ impl<'a> Seek for WiiPartReadStream<'a> {
             SeekFrom::End(v) => (self.stable_stream_len()? as i64 + v) as u64,
             SeekFrom::Current(v) => (self.offset as i64 + v) as u64,
         };
-        let block = self.offset / BLOCK_SIZE as u64;
+        let block = (self.offset / BLOCK_SIZE as u64) as u32;
         if block != self.cur_block {
-            self.stream.seek(SeekFrom::Start(block * BUFFER_SIZE as u64))?;
+            self.stream.seek(SeekFrom::Start(block as u64 * SECTOR_SIZE as u64))?;
-            self.cur_block = u64::MAX;
+            self.cur_block = u32::MAX;
         }
-        io::Result::Ok(self.offset)
+        Ok(self.offset)
     }
 
-    fn stream_position(&mut self) -> io::Result<u64> { io::Result::Ok(self.offset) }
+    fn stream_position(&mut self) -> io::Result<u64> { Ok(self.offset) }
 }
 
 impl<'a> ReadStream for WiiPartReadStream<'a> {
     fn stable_stream_len(&mut self) -> io::Result<u64> {
-        io::Result::Ok(to_block_size(self.stream.stable_stream_len()?))
+        Ok(to_block_size(self.stream.stable_stream_len()?))
     }
 
     fn as_dyn(&mut self) -> &mut dyn ReadStream { self }
 }
 
-#[derive(Clone, Debug, PartialEq, BinRead)]
+#[derive(Clone, Debug, PartialEq)]
 pub(crate) struct WiiPartition {
     header: Header,
-    bi2_header: BI2Header,
+    // #[br(seek_before = SeekFrom::Start(0x400))]
-    #[br(seek_before = SeekFrom::Start((header.fst_off as u64) << 2))]
+    part_header: PartitionHeader,
-    #[br(parse_with = node_parser)]
+    // bi2_header: BI2Header,
+    // #[br(seek_before = SeekFrom::Start((part_header.fst_off as u64) << 2))]
+    // #[br(parse_with = node_parser)]
     root_node: NodeType,
 }
 
@@ -420,4 +562,22 @@ impl PartHeader for WiiPartition {
     fn root_node(&self) -> &NodeType { &self.root_node }
 
     fn find_node(&self, path: &str) -> Option<&NodeType> { find_node(&self.root_node, path) }
+
+    fn boot_bytes(&self) -> &[u8] { todo!() }
+
+    fn bi2_bytes(&self) -> &[u8] { todo!() }
+
+    fn apploader_bytes(&self) -> &[u8] { todo!() }
+
+    fn fst_bytes(&self) -> &[u8] { todo!() }
+
+    fn dol_bytes(&self) -> &[u8] { todo!() }
+
+    fn disc_header(&self) -> &Header { todo!() }
+
+    fn partition_header(&self) -> &PartitionHeader { todo!() }
+
+    fn apploader_header(&self) -> &AppLoaderHeader { todo!() }
+
+    fn dol_header(&self) -> &DolHeader { todo!() }
 }

src/fst.rs

@@ -1,10 +1,18 @@
 //! Disc file system types
 
-use std::io::{Read, Seek, SeekFrom};
+use std::{
+    ffi::CString,
+    io,
+    io::{Read, Seek, SeekFrom},
+};
 
-use binrw::{binread, BinReaderExt, BinResult, NullString, ReadOptions};
 use encoding_rs::SHIFT_JIS;
 
+use crate::{
+    util::reader::{struct_size, FromReader, DYNAMIC_SIZE, U24},
+    Result, ResultContext,
+};
+
 /// File system node kind.
 #[derive(Clone, Debug, PartialEq)]
 pub enum NodeKind {
@@ -14,17 +22,30 @@ pub enum NodeKind {
     Directory,
 }
 
+impl FromReader for NodeKind {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = 1;
+
+    fn from_reader_args<R>(_reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        match u8::from_reader(_reader)? {
+            0 => Ok(NodeKind::File),
+            1 => Ok(NodeKind::Directory),
+            _ => Err(io::Error::new(io::ErrorKind::InvalidData, "invalid node kind")),
+        }
+    }
+}
+
 /// An individual file system node.
-#[binread]
 #[derive(Clone, Debug, PartialEq)]
 pub struct Node {
-    #[br(temp)]
-    type_and_name_offset: u32,
-
     /// File system node type.
-    #[br(calc = if (type_and_name_offset >> 24) != 0 { NodeKind::Directory } else { NodeKind::File })]
     pub kind: NodeKind,
 
+    /// Offset in the string table to the filename.
+    pub name_offset: u32,
+
     /// For files, this is the partition offset of the file data. (Wii: >> 2)
     ///
     /// For directories, this is the children start offset in the FST.
@@ -37,11 +58,28 @@ pub struct Node {
     /// Number of child files and directories recursively is `length - offset`.
     pub length: u32,
 
-    #[br(calc = type_and_name_offset & 0xffffff)]
-    name_offset: u32,
-    #[br(ignore)]
     /// The node name.
-    pub name: Box<str>,
+    pub name: String,
+}
+
+impl FromReader for Node {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = struct_size([
+        NodeKind::STATIC_SIZE, // type
+        U24::STATIC_SIZE,      // name_offset
+        u32::STATIC_SIZE,      // offset
+        u32::STATIC_SIZE,      // length
+    ]);
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        let kind = NodeKind::from_reader(reader)?;
+        let name_offset = U24::from_reader(reader)?.0;
+        let offset = u32::from_reader(reader)?;
+        let length = u32::from_reader(reader)?;
+        Ok(Node { kind, offset, length, name_offset, name: Default::default() })
+    }
 }
 
 /// Contains a file system node, and if a directory, its children.
@@ -53,74 +91,77 @@ pub enum NodeType {
     Directory(Node, Vec<NodeType>),
 }
 
-fn read_node<R: Read + Seek>(reader: &mut R, ro: &ReadOptions, i: &mut u32) -> BinResult<NodeType> {
+impl FromReader for NodeType {
-    let node = reader.read_type::<Node>(ro.endian())?;
+    type Args<'a> = &'a mut u32;
-    *i += 1;
+
-    BinResult::Ok(if node.kind == NodeKind::Directory {
+    const STATIC_SIZE: usize = DYNAMIC_SIZE;
-        let mut children: Vec<NodeType> = Vec::new();
+
-        children.reserve((node.length - *i) as usize);
+    fn from_reader_args<R>(reader: &mut R, idx: &mut u32) -> io::Result<Self>
-        while *i < node.length {
+    where R: Read + ?Sized {
-            children.push(read_node(reader, ro, i)?);
+        let node = Node::from_reader(reader)?;
-        }
+        *idx += 1;
-        NodeType::Directory(node, children)
+        Ok(if node.kind == NodeKind::Directory {
-    } else {
+            let mut children = Vec::with_capacity((node.length - *idx) as usize);
-        NodeType::File(node)
+            while *idx < node.length {
-    })
+                children.push(NodeType::from_reader_args(reader, idx)?);
+            }
+            NodeType::Directory(node, children)
+        } else {
+            NodeType::File(node)
+        })
+    }
 }
 
-fn read_node_name<R: Read + Seek>(
+fn read_node_name<R>(
     reader: &mut R,
-    ro: &ReadOptions,
+    string_base: u64,
-    base: u64,
     node: &mut NodeType,
     root: bool,
-) -> BinResult<()> {
+) -> io::Result<()>
-    let mut decode_name = |v: &mut Node| -> BinResult<()> {
+where
+    R: Read + Seek + ?Sized,
+{
+    let mut decode_name = |v: &mut Node| -> io::Result<()> {
         if !root {
-            let offset = base + v.name_offset as u64;
+            let offset = string_base + v.name_offset as u64;
             reader.seek(SeekFrom::Start(offset))?;
-            let null_string = reader.read_type::<NullString>(ro.endian())?;
+
-            let (res, _, errors) = SHIFT_JIS.decode(&*null_string.0);
+            let c_string = CString::from_reader(reader)?;
+            let (decoded, _, errors) = SHIFT_JIS.decode(c_string.as_bytes());
             if errors {
-                return BinResult::Err(binrw::Error::Custom {
+                return Err(io::Error::new(io::ErrorKind::InvalidData, "invalid shift-jis"));
-                    pos: offset,
-                    err: Box::new("Failed to decode node name"),
-                });
             }
-            v.name = res.into();
+            v.name = decoded.into_owned();
         }
-        BinResult::Ok(())
+        Ok(())
     };
     match node {
-        NodeType::File(v) => {
+        NodeType::File(inner) => {
-            decode_name(v)?;
+            decode_name(inner)?;
         }
-        NodeType::Directory(v, c) => {
+        NodeType::Directory(inner, children) => {
-            decode_name(v)?;
+            decode_name(inner)?;
-            for x in c {
+            for child in children {
-                read_node_name(reader, ro, base, x, false)?;
+                read_node_name(reader, string_base, child, false)?;
             }
         }
     }
-    BinResult::Ok(())
+    Ok(())
 }
 
-pub(crate) fn node_parser<R: Read + Seek>(
+pub(crate) fn read_fst<R>(reader: &mut R) -> Result<NodeType>
-    reader: &mut R,
+where R: Read + Seek + ?Sized {
-    ro: &ReadOptions,
+    let mut node = NodeType::from_reader_args(reader, &mut 0).context("Parsing FST nodes")?;
-    _: (),
+    let string_base = reader.stream_position().context("Reading FST end position")?;
-) -> BinResult<NodeType> {
+    read_node_name(reader, string_base, &mut node, true).context("Reading FST node names")?;
-    let mut node = read_node(reader, ro, &mut 0)?;
+    Ok(node)
-    let base = reader.stream_position()?;
-    read_node_name(reader, ro, base, &mut node, true)?;
-    BinResult::Ok(node)
 }
 
 fn matches_name(node: &NodeType, name: &str) -> bool {
     match node {
-        NodeType::File(v) => v.name.as_ref().eq_ignore_ascii_case(name),
+        NodeType::File(v) => v.name.as_str().eq_ignore_ascii_case(name),
         NodeType::Directory(v, _) => {
-            v.name.is_empty() /* root */ || v.name.as_ref().eq_ignore_ascii_case(name)
+            v.name.is_empty() /* root */ || v.name.as_str().eq_ignore_ascii_case(name)
         }
     }
 }
@@ -132,7 +173,7 @@ pub(crate) fn find_node<'a>(mut node: &'a NodeType, path: &str) -> Option<&'a No
         if matches_name(node, current.unwrap()) {
             match node {
                 NodeType::File(_) => {
-                    return if split.next().is_none() { Option::Some(node) } else { Option::None };
+                    return if split.next().is_none() { Some(node) } else { None };
                 }
                 NodeType::Directory(v, c) => {
                     // Find child
@@ -140,11 +181,7 @@ pub(crate) fn find_node<'a>(mut node: &'a NodeType, path: &str) -> Option<&'a No
                         current = split.next();
                     }
                     if current.is_none() || current.unwrap().is_empty() {
-                        return if split.next().is_none() {
+                        return if split.next().is_none() { Some(node) } else { None };
-                            Option::Some(node)
-                        } else {
-                            Option::None
-                        };
                     }
                     for x in c {
                         if matches_name(x, current.unwrap()) {
@@ -158,5 +195,5 @@ pub(crate) fn find_node<'a>(mut node: &'a NodeType, path: &str) -> Option<&'a No
             break;
         }
     }
-    Option::None
+    None
 }

src/io/iso.rs

@@ -13,7 +13,7 @@ pub(crate) struct DiscIOISO {
 
 impl DiscIOISO {
     pub(crate) fn new(filename: &Path) -> Result<DiscIOISO> {
-        Result::Ok(DiscIOISO { filename: filename.to_owned() })
+        Ok(DiscIOISO { filename: filename.to_owned() })
     }
 }
 
@@ -21,21 +21,25 @@ impl DiscIO for DiscIOISO {
     fn begin_read_stream(&mut self, offset: u64) -> io::Result<Box<dyn ReadStream>> {
         let mut file = File::open(&*self.filename)?;
         file.seek(SeekFrom::Start(offset))?;
-        io::Result::Ok(Box::from(file))
+        Ok(Box::from(file))
     }
 }
 
-pub(crate) struct DiscIOISOStream<T: ReadStream + Sized> {
+pub(crate) struct DiscIOISOStream<T>
+where T: ReadStream + Sized
+{
     pub(crate) stream: T,
 }
 
-impl<T: ReadStream + Sized> DiscIOISOStream<T> {
+impl<T> DiscIOISOStream<T>
-    pub(crate) fn new(stream: T) -> Result<DiscIOISOStream<T>> {
+where T: ReadStream + Sized
-        Result::Ok(DiscIOISOStream { stream })
+{
-    }
+    pub(crate) fn new(stream: T) -> Result<DiscIOISOStream<T>> { Ok(DiscIOISOStream { stream }) }
 }
 
-impl<T: ReadStream + Sized + Send + Sync> DiscIO for DiscIOISOStream<T> {
+impl<T> DiscIO for DiscIOISOStream<T>
+where T: ReadStream + Sized + Send + Sync
+{
     fn begin_read_stream<'a>(&'a mut self, offset: u64) -> io::Result<Box<dyn ReadStream + 'a>> {
         let size = self.stream.stable_stream_len()?;
         let mut stream = self.stream.new_window(0, size)?;

src/io/mod.rs

@@ -6,6 +6,7 @@ use crate::{
     io::{
         iso::{DiscIOISO, DiscIOISOStream},
         nfs::DiscIONFS,
+        wia::DiscIOWIA,
     },
     streams::{ByteReadStream, ReadStream},
     Error, Result,
@@ -13,6 +14,13 @@ use crate::{
 
 pub(crate) mod iso;
 pub(crate) mod nfs;
+pub(crate) mod wia;
+
+#[derive(Default, Debug, Clone)]
+pub struct DiscIOOptions {
+    /// Rebuild hashes for the disc image.
+    pub rebuild_hashes: bool,
+}
 
 /// Abstraction over supported disc file types.
 pub trait DiscIO: Send + Sync {
@@ -30,43 +38,40 @@ pub trait DiscIO: Send + Sync {
 ///
 /// Basic usage:
 /// ```no_run
-/// use nod::io::new_disc_io;
+/// use nod::io::{new_disc_io, DiscIOOptions};
 ///
-/// let mut disc_io = new_disc_io("path/to/file".as_ref())?;
+/// # fn main() -> nod::Result<()> {
-/// # Ok::<(), nod::Error>(())
+/// let options = DiscIOOptions::default();
+/// let mut disc_io = new_disc_io("path/to/file.iso".as_ref(), &options)?;
+/// # Ok(())
+/// # }
 /// ```
-pub fn new_disc_io(filename: &Path) -> Result<Box<dyn DiscIO>> {
+pub fn new_disc_io(filename: &Path, options: &DiscIOOptions) -> Result<Box<dyn DiscIO>> {
     let path_result = fs::canonicalize(filename);
     if let Err(err) = path_result {
-        return Result::Err(Error::Io(
+        return Err(Error::Io(format!("Failed to open {}", filename.display()), err));
-            format!("Failed to open {}", filename.to_string_lossy()),
-            err,
-        ));
     }
     let path = path_result.as_ref().unwrap();
     let meta = fs::metadata(path);
     if let Err(err) = meta {
-        return Result::Err(Error::Io(
+        return Err(Error::Io(format!("Failed to open {}", filename.display()), err));
-            format!("Failed to open {}", filename.to_string_lossy()),
-            err,
-        ));
     }
     if !meta.unwrap().is_file() {
-        return Result::Err(Error::DiscFormat(format!(
+        return Err(Error::DiscFormat(format!("Input is not a file: {}", filename.display())));
-            "Input is not a file: {}",
-            filename.to_string_lossy()
-        )));
     }
     if has_extension(path, "iso") {
-        Result::Ok(Box::from(DiscIOISO::new(path)?))
+        Ok(Box::from(DiscIOISO::new(path)?))
     } else if has_extension(path, "nfs") {
-        if matches!(path.parent(), Some(parent) if parent.is_dir()) {
+        match path.parent() {
-            Result::Ok(Box::from(DiscIONFS::new(path.parent().unwrap())?))
+            Some(parent) if parent.is_dir() => {
-        } else {
+                Ok(Box::from(DiscIONFS::new(path.parent().unwrap())?))
-            Result::Err(Error::DiscFormat("Failed to locate NFS parent directory".to_string()))
+            }
+            _ => Err(Error::DiscFormat("Failed to locate NFS parent directory".to_string())),
         }
+    } else if has_extension(path, "wia") || has_extension(path, "rvz") {
+        Ok(Box::from(DiscIOWIA::new(path, options)?))
     } else {
-        Result::Err(Error::DiscFormat("Unknown file type".to_string()))
+        Err(Error::DiscFormat("Unknown file type".to_string()))
     }
 }
 
@@ -78,9 +83,11 @@ pub fn new_disc_io(filename: &Path) -> Result<Box<dyn DiscIO>> {
 /// ```no_run
 /// use nod::io::new_disc_io_from_buf;
 ///
-/// # #[allow(non_upper_case_globals)] const buf: [u8; 0] = [];
+/// # fn main() -> nod::Result<()> {
-/// let mut disc_io = new_disc_io_from_buf(&buf)?;
+/// # #[allow(non_upper_case_globals)] const buf: &[u8] = &[0u8; 0];
-/// # Ok::<(), nod::Error>(())
+/// let mut disc_io = new_disc_io_from_buf(buf)?;
+/// # Ok(())
+/// # }
 /// ```
 pub fn new_disc_io_from_buf(buf: &[u8]) -> Result<Box<dyn DiscIO + '_>> {
     new_disc_io_from_stream(ByteReadStream { bytes: buf, position: 0 })
@@ -92,11 +99,15 @@ pub fn new_disc_io_from_buf(buf: &[u8]) -> Result<Box<dyn DiscIO + '_>> {
 ///
 /// Basic usage:
 /// ```no_run
-/// use nod::io::new_disc_io_from_buf;
+/// use nod::io::new_disc_io_from_stream;
+/// use nod::streams::ByteReadStream;
 ///
-/// # #[allow(non_upper_case_globals)] const buf: [u8; 0] = [];
+/// # fn main() -> nod::Result<()> {
-/// let mut disc_io = new_disc_io_from_buf(&buf)?;
+/// # #[allow(non_upper_case_globals)] const buf: &[u8] = &[0u8; 0];
-/// # Ok::<(), nod::Error>(())
+/// let stream = ByteReadStream { bytes: buf, position: 0 };
+/// let mut disc_io = new_disc_io_from_stream(stream)?;
+/// # Ok(())
+/// # }
 /// ```
 pub fn new_disc_io_from_stream<'a, T: 'a + ReadStream + Sized + Send + Sync>(
     stream: T,
@@ -107,11 +118,8 @@ pub fn new_disc_io_from_stream<'a, T: 'a + ReadStream + Sized + Send + Sync>(
 /// Helper function for checking a file extension.
 #[inline(always)]
 pub fn has_extension(filename: &Path, extension: &str) -> bool {
-    if let Some(ext) = filename.extension() {
+    match filename.extension() {
-        // TODO use with Rust 1.53+
+        Some(ext) => ext.eq_ignore_ascii_case(extension),
-        // ext.eq_ignore_ascii_case(extension)
+        None => false,
-        ext.to_str().unwrap_or("").eq_ignore_ascii_case(extension)
-    } else {
-        false
     }
 }

src/io/nfs.rs

@@ -1,36 +1,87 @@
 use std::{
     fs::File,
     io,
-    io::{Read, Seek, SeekFrom},
+    io::{BufReader, Read, Seek, SeekFrom},
     path::{Component, Path, PathBuf},
 };
 
-use aes::{Aes128, NewBlockCipher};
+use aes::{
-use binrw::{binread, BinRead, BinReaderExt};
+    cipher::{block_padding::NoPadding, BlockDecryptMut, KeyIvInit},
-use block_modes::{block_padding::NoPadding, BlockMode, Cbc};
+    Aes128,
+};
 
-use crate::{disc::BUFFER_SIZE, io::DiscIO, streams::ReadStream, Error, Result};
+use crate::{
+    disc::SECTOR_SIZE,
+    io::DiscIO,
+    streams::ReadStream,
+    util::reader::{read_vec, struct_size, FromReader},
+    Error, Result, ResultContext,
+};
 
-type Aes128Cbc = Cbc<Aes128, NoPadding>;
+type Aes128Cbc = cbc::Decryptor<Aes128>;
 
-#[derive(Clone, Debug, PartialEq, BinRead)]
+#[derive(Clone, Debug, PartialEq)]
 pub(crate) struct LBARange {
     pub(crate) start_block: u32,
     pub(crate) num_blocks: u32,
 }
 
-#[binread]
+impl FromReader for LBARange {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = struct_size([
+        u32::STATIC_SIZE, // start_block
+        u32::STATIC_SIZE, // num_blocks
+    ]);
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        Ok(LBARange {
+            start_block: u32::from_reader(reader)?,
+            num_blocks: u32::from_reader(reader)?,
+        })
+    }
+}
+
+type MagicBytes = [u8; 4];
+
 #[derive(Clone, Debug, PartialEq)]
-#[br(magic = b"EGGS", assert(end_magic == * b"SGGE"))]
 pub(crate) struct NFSHeader {
     pub(crate) version: u32,
     pub(crate) unk1: u32,
     pub(crate) unk2: u32,
-    pub(crate) lba_range_count: u32,
-    #[br(count = 61)]
     pub(crate) lba_ranges: Vec<LBARange>,
-    #[br(temp)]
+}
-    pub(crate) end_magic: [u8; 4],
+
+impl FromReader for NFSHeader {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = struct_size([
+        MagicBytes::STATIC_SIZE,    // magic
+        u32::STATIC_SIZE,           // version
+        u32::STATIC_SIZE,           // unk1
+        u32::STATIC_SIZE,           // unk2
+        u32::STATIC_SIZE,           // lba_range_count
+        LBARange::STATIC_SIZE * 61, // lba_ranges
+        MagicBytes::STATIC_SIZE,    // end_magic
+    ]);
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        if MagicBytes::from_reader(reader)? != *b"EGGS" {
+            return Err(io::Error::new(io::ErrorKind::InvalidData, "Invalid NFS magic"));
+        }
+        let version = u32::from_reader(reader)?;
+        let unk1 = u32::from_reader(reader)?;
+        let unk2 = u32::from_reader(reader)?;
+        let lba_range_count = u32::from_reader(reader)?;
+        let mut lba_ranges = read_vec(reader, 61)?;
+        lba_ranges.truncate(lba_range_count as usize);
+        if MagicBytes::from_reader(reader)? != *b"SGGE" {
+            return Err(io::Error::new(io::ErrorKind::InvalidData, "Invalid NFS end magic"));
+        }
+        Ok(NFSHeader { version, unk1, unk2, lba_ranges })
+    }
 }
 
 #[derive(Clone, Copy, Debug, PartialEq)]
@@ -49,11 +100,8 @@ impl Default for Fbo {
 
 impl NFSHeader {
     pub(crate) fn calculate_num_files(&self) -> u32 {
-        let total_block_count = self
+        let total_block_count =
-            .lba_ranges
+            self.lba_ranges.iter().fold(0u32, |acc, range| acc + range.num_blocks);
-            .iter()
-            .take(self.lba_range_count as usize)
-            .fold(0u32, |acc, range| acc + range.num_blocks);
         (((total_block_count as u64) * 0x8000u64 + (0x200u64 + 0xF9FFFFFu64)) / 0xFA00000u64) as u32
     }
 
@@ -62,7 +110,7 @@ impl NFSHeader {
         let block_off = (offset % 0x8000) as u32;
         let mut block = u32::MAX;
         let mut physical_block = 0u32;
-        for range in self.lba_ranges.iter().take(self.lba_range_count as usize) {
+        for range in self.lba_ranges.iter() {
             if block_div >= range.start_block && block_div - range.start_block < range.num_blocks {
                 block = physical_block + (block_div - range.start_block);
                 break;
@@ -85,17 +133,16 @@ pub(crate) struct DiscIONFS {
 
 impl DiscIONFS {
     pub(crate) fn new(directory: &Path) -> Result<DiscIONFS> {
-        let mut disc_io =
+        let mut disc_io = DiscIONFS { directory: directory.to_owned(), key: [0; 16], header: None };
-            DiscIONFS { directory: directory.to_owned(), key: [0; 16], header: Option::None };
         disc_io.validate_files()?;
-        Result::Ok(disc_io)
+        Ok(disc_io)
     }
 }
 
 pub(crate) struct NFSReadStream<'a> {
     disc_io: &'a DiscIONFS,
     file: Option<File>,
-    crypto: Aes128,
+    crypto: [u8; 16],
     // Physical address - all UINT32_MAX indicates logical zero block
     phys_addr: Fbo,
     // Logical address
@@ -104,18 +151,21 @@ pub(crate) struct NFSReadStream<'a> {
     // Block is typically one ahead of the presently decrypted block.
     cur_file: u32,
     cur_block: u32,
-    buf: [u8; BUFFER_SIZE],
+    buf: [u8; SECTOR_SIZE],
 }
 
 impl<'a> NFSReadStream<'a> {
     fn set_cur_file(&mut self, cur_file: u32) -> Result<()> {
         if cur_file >= self.disc_io.header.as_ref().unwrap().calculate_num_files() {
-            return Result::Err(Error::DiscFormat("Out of bounds NFS file access".to_string()));
+            return Err(Error::DiscFormat(format!("Out of bounds NFS file access: {}", cur_file)));
         }
         self.cur_file = cur_file;
         self.cur_block = u32::MAX;
-        self.file = Option::from(File::open(self.disc_io.get_nfs(cur_file)?)?);
+        let path = self.disc_io.get_nfs(cur_file)?;
-        Result::Ok(())
+        self.file = Option::from(
+            File::open(&path).with_context(|| format!("Opening file {}", path.display()))?,
+        );
+        Ok(())
     }
 
     fn set_cur_block(&mut self, cur_block: u32) -> io::Result<()> {
@@ -123,22 +173,22 @@ impl<'a> NFSReadStream<'a> {
         self.file
             .as_ref()
             .unwrap()
-            .seek(SeekFrom::Start(self.cur_block as u64 * BUFFER_SIZE as u64 + 0x200u64))?;
+            .seek(SeekFrom::Start(self.cur_block as u64 * SECTOR_SIZE as u64 + 0x200u64))?;
-        io::Result::Ok(())
+        Ok(())
     }
 
     fn set_phys_addr(&mut self, phys_addr: Fbo) -> Result<()> {
         // If we're just changing the offset, nothing else needs to be done
         if self.phys_addr.file == phys_addr.file && self.phys_addr.block == phys_addr.block {
             self.phys_addr.offset = phys_addr.offset;
-            return Result::Ok(());
+            return Ok(());
         }
         self.phys_addr = phys_addr;
 
         // Set logical zero block
         if phys_addr.file == u32::MAX {
             self.buf.fill(0u8);
-            return Result::Ok(());
+            return Ok(());
         }
 
         // Make necessary file and block current with system
@@ -146,17 +196,30 @@ impl<'a> NFSReadStream<'a> {
             self.set_cur_file(phys_addr.file)?;
         }
         if phys_addr.block != self.cur_block {
-            self.set_cur_block(phys_addr.block)?;
+            self.set_cur_block(phys_addr.block)
+                .with_context(|| format!("Seeking to NFS block {}", phys_addr.block))?;
         }
 
         // Read block, handling 0x200 overlap case
         if phys_addr.block == 7999 {
-            self.file.as_ref().unwrap().read_exact(&mut self.buf[..BUFFER_SIZE - 0x200])?;
+            self.file
+                .as_ref()
+                .unwrap()
+                .read_exact(&mut self.buf[..SECTOR_SIZE - 0x200])
+                .context("Reading NFS block 7999 part 1")?;
             self.set_cur_file(self.cur_file + 1)?;
-            self.file.as_ref().unwrap().read_exact(&mut self.buf[BUFFER_SIZE - 0x200..])?;
+            self.file
+                .as_ref()
+                .unwrap()
+                .read_exact(&mut self.buf[SECTOR_SIZE - 0x200..])
+                .context("Reading NFS block 7999 part 2")?;
             self.cur_block = 0;
         } else {
-            self.file.as_ref().unwrap().read_exact(&mut self.buf)?;
+            self.file
+                .as_ref()
+                .unwrap()
+                .read_exact(&mut self.buf)
+                .with_context(|| format!("Reading NFS block {}", phys_addr.block))?;
             self.cur_block += 1;
         }
 
@@ -169,9 +232,10 @@ impl<'a> NFSReadStream<'a> {
             ((phys_addr.l_block >> 16) & 0xFF) as u8,
             ((phys_addr.l_block >> 24) & 0xFF) as u8,
         ];
-        Aes128Cbc::new(self.crypto.clone(), &iv.into()).decrypt(&mut self.buf)?;
+        Aes128Cbc::new(self.crypto.as_ref().into(), &iv.into())
+            .decrypt_padded_mut::<NoPadding>(&mut self.buf)?;
 
-        Result::Ok(())
+        Ok(())
     }
 
     fn set_logical_addr(&mut self, addr: u64) -> Result<()> {
@@ -187,20 +251,20 @@ impl<'a> Read for NFSReadStream<'a> {
             let mut read_size = rem;
             let block_offset: usize =
                 if self.phys_addr.offset == u32::MAX { 0 } else { self.phys_addr.offset as usize };
-            if read_size + block_offset > BUFFER_SIZE {
+            if read_size + block_offset > SECTOR_SIZE {
-                read_size = BUFFER_SIZE - block_offset
+                read_size = SECTOR_SIZE - block_offset
             }
             buf[read..read + read_size]
                 .copy_from_slice(&self.buf[block_offset..block_offset + read_size]);
             read += read_size;
             rem -= read_size;
             self.offset += read_size as u64;
-            self.set_logical_addr(self.offset).map_err(|v| match v {
+            self.set_logical_addr(self.offset).map_err(|e| match e {
-                Error::Io(_, v) => v,
+                Error::Io(s, e) => io::Error::new(e.kind(), s),
                 _ => io::Error::from(io::ErrorKind::Other),
             })?;
         }
-        io::Result::Ok(read)
+        Ok(read)
     }
 }
 
@@ -215,10 +279,10 @@ impl<'a> Seek for NFSReadStream<'a> {
             Error::Io(_, v) => v,
             _ => io::Error::from(io::ErrorKind::Other),
         })?;
-        io::Result::Ok(self.offset)
+        Ok(self.offset)
     }
 
-    fn stream_position(&mut self) -> io::Result<u64> { io::Result::Ok(self.offset) }
+    fn stream_position(&mut self) -> io::Result<u64> { Ok(self.offset) }
 }
 
 impl<'a> ReadStream for NFSReadStream<'a> {
@@ -229,15 +293,15 @@ impl<'a> ReadStream for NFSReadStream<'a> {
 
 impl DiscIO for DiscIONFS {
     fn begin_read_stream(&mut self, offset: u64) -> io::Result<Box<dyn ReadStream + '_>> {
-        io::Result::Ok(Box::from(NFSReadStream {
+        Ok(Box::from(NFSReadStream {
             disc_io: self,
-            file: Option::None,
+            file: None,
-            crypto: Aes128::new(&self.key.into()),
+            crypto: self.key,
             phys_addr: Fbo::default(),
             offset,
             cur_file: u32::MAX,
             cur_block: u32::MAX,
-            buf: [0; BUFFER_SIZE],
+            buf: [0; SECTOR_SIZE],
         }))
     }
 
@@ -245,7 +309,8 @@ impl DiscIO for DiscIONFS {
 }
 
 impl DiscIONFS {
-    fn get_path<P: AsRef<Path>>(&self, path: P) -> PathBuf {
+    fn get_path<P>(&self, path: P) -> PathBuf
+    where P: AsRef<Path> {
         let mut buf = self.directory.clone();
         for component in path.as_ref().components() {
             match component {
@@ -261,9 +326,9 @@ impl DiscIONFS {
     fn get_nfs(&self, num: u32) -> Result<PathBuf> {
         let path = self.get_path(format!("hif_{:06}.nfs", num));
         if path.exists() {
-            Result::Ok(path)
+            Ok(path)
         } else {
-            Result::Err(Error::DiscFormat(format!("Failed to locate {}", path.to_string_lossy())))
+            Err(Error::DiscFormat(format!("Failed to locate {}", path.display())))
         }
     }
 
@@ -278,31 +343,32 @@ impl DiscIONFS {
                 key_path = secondary_key_path.canonicalize();
             }
             if key_path.is_err() {
-                return Result::Err(Error::DiscFormat(format!(
+                return Err(Error::DiscFormat(format!(
                     "Failed to locate {} or {}",
-                    primary_key_path.to_string_lossy(),
+                    primary_key_path.display(),
-                    secondary_key_path.to_string_lossy()
+                    secondary_key_path.display()
                 )));
             }
             let resolved_path = key_path.unwrap();
             File::open(resolved_path.as_path())
-                .map_err(|v| {
+                .map_err(|v| Error::Io(format!("Failed to open {}", resolved_path.display()), v))?
-                    Error::Io(format!("Failed to open {}", resolved_path.to_string_lossy()), v)
-                })?
                 .read(&mut self.key)
-                .map_err(|v| {
+                .map_err(|v| Error::Io(format!("Failed to read {}", resolved_path.display()), v))?;
-                    Error::Io(format!("Failed to read {}", resolved_path.to_string_lossy()), v)
-                })?;
         }
         {
             // Load header from first file
-            let header: NFSHeader = File::open(self.get_nfs(0)?)?.read_be()?;
+            let path = self.get_nfs(0)?;
+            let mut file = BufReader::new(
+                File::open(&path).with_context(|| format!("Opening file {}", path.display()))?,
+            );
+            let header = NFSHeader::from_reader(&mut file)
+                .with_context(|| format!("Reading NFS header from file {}", path.display()))?;
             // Ensure remaining files exist
             for i in 1..header.calculate_num_files() {
                 self.get_nfs(i)?;
             }
-            self.header = Option::from(header)
+            self.header = Option::from(header);
         }
-        Result::Ok(())
+        Ok(())
     }
 }

src/lib.rs

@@ -1,71 +1,93 @@
-#![warn(missing_docs)]
+#![warn(missing_docs, rustdoc::missing_doc_code_examples)]
-#![warn(rustdoc::missing_doc_code_examples)]
 //! Library for traversing & reading GameCube and Wii disc images.
 //!
 //! Based on the C++ library [nod](https://github.com/AxioDL/nod),
 //! but does not currently support authoring.
 //!
 //! Currently supported file formats:
-//! - ISO
+//! - ISO (GCM)
+//! - WIA / RVZ
+//! - WBFS
 //! - NFS (Wii U VC files, e.g. `hif_000000.nfs`)
 //!
 //! # Examples
 //!
 //! Opening a disc image and reading a file:
 //! ```no_run
-//! use nod::disc::{new_disc_base, PartHeader};
-//! use nod::fst::NodeType;
-//! use nod::io::new_disc_io;
 //! use std::io::Read;
 //!
-//! let mut disc_io = new_disc_io("path/to/file".as_ref())?;
+//! use nod::{
-//! let disc_base = new_disc_base(disc_io.as_mut())?;
+//!     disc::{new_disc_base, PartHeader},
-//! let mut partition = disc_base.get_data_partition(disc_io.as_mut(), false)?;
+//!     fst::NodeType,
-//! let header = partition.read_header()?;
+//!     io::{new_disc_io, DiscIOOptions},
-//! if let Some(NodeType::File(node)) = header.find_node("/MP3/Worlds.txt") {
+//! };
-//!     let mut s = String::new();
+//!
-//!     partition.begin_file_stream(node)?.read_to_string(&mut s);
+//! fn main() -> nod::Result<()> {
-//!     println!("{}", s);
+//!     let options = DiscIOOptions::default();
+//!     let mut disc_io = new_disc_io("path/to/file.iso".as_ref(), &options)?;
+//!     let disc_base = new_disc_base(disc_io.as_mut())?;
+//!     let mut partition = disc_base.get_data_partition(disc_io.as_mut(), false)?;
+//!     let header = partition.read_header()?;
+//!     if let Some(NodeType::File(node)) = header.find_node("/MP3/Worlds.txt") {
+//!         let mut s = String::new();
+//!         partition.begin_file_stream(node)?.read_to_string(&mut s).expect("Failed to read file");
+//!         println!("{}", s);
+//!     }
+//!     Ok(())
 //! }
-//! # Ok::<(), nod::Error>(())
 //! ```
-use thiserror::Error;
-
 pub mod disc;
 pub mod fst;
 pub mod io;
 pub mod streams;
+pub mod util;
 
 /// Error types for nod.
-#[derive(Error, Debug)]
+#[derive(thiserror::Error, Debug)]
 pub enum Error {
-    /// An error during binary format parsing.
-    #[error("binary format")]
-    BinaryFormat(#[from] binrw::Error),
-    /// An error during Wii disc decryption.
-    #[error("encryption")]
-    Encryption(#[from] block_modes::BlockModeError),
-    /// A general I/O error.
-    #[error("io error: `{0}`")]
-    Io(String, #[source] std::io::Error),
     /// An error for disc format related issues.
-    #[error("disc format error: `{0}`")]
+    #[error("disc format error: {0}")]
     DiscFormat(String),
+    /// A general I/O error.
+    #[error("I/O error: {0}")]
+    Io(String, #[source] std::io::Error),
 }
 
-/// Helper result type for [`enum@Error`].
+/// Helper result type for [`Error`].
 pub type Result<T, E = Error> = core::result::Result<T, E>;
 
-impl From<std::io::Error> for Error {
+impl From<aes::cipher::block_padding::UnpadError> for Error {
-    fn from(v: std::io::Error) -> Self { Error::Io("I/O error".to_string(), v) }
+    fn from(_: aes::cipher::block_padding::UnpadError) -> Self { unreachable!() }
 }
 
-#[inline(always)]
+impl From<base16ct::Error> for Error {
-pub(crate) fn div_rem<T: std::ops::Div<Output = T> + std::ops::Rem<Output = T> + Copy>(
+    fn from(_: base16ct::Error) -> Self { unreachable!() }
-    x: T,
+}
-    y: T,
+
-) -> (T, T) {
+pub trait ErrorContext {
-    let quot = x / y;
+    fn context(self, context: impl Into<String>) -> Error;
-    let rem = x % y;
+}
-    (quot, rem)
+
+impl ErrorContext for std::io::Error {
+    fn context(self, context: impl Into<String>) -> Error { Error::Io(context.into(), self) }
+}
+
+pub trait ResultContext<T> {
+    fn context(self, context: impl Into<String>) -> Result<T>;
+
+    fn with_context<F>(self, f: F) -> Result<T>
+    where F: FnOnce() -> String;
+}
+
+impl<T, E> ResultContext<T> for Result<T, E>
+where E: ErrorContext
+{
+    fn context(self, context: impl Into<String>) -> Result<T> {
+        self.map_err(|e| e.context(context))
+    }
+
+    fn with_context<F>(self, f: F) -> Result<T>
+    where F: FnOnce() -> String {
+        self.map_err(|e| e.context(f()))
+    }
 }

src/streams.rs

@@ -43,11 +43,7 @@ pub trait ReadStream: Read + Seek {
     /// Seeks underlying stream immediately.
     fn new_window(&mut self, offset: u64, size: u64) -> io::Result<SharedWindowedReadStream> {
         self.seek(SeekFrom::Start(offset))?;
-        io::Result::Ok(SharedWindowedReadStream {
+        Ok(SharedWindowedReadStream { base: self.as_dyn(), begin: offset, end: offset + size })
-            base: self.as_dyn(),
-            begin: offset,
-            end: offset + size,
-        })
     }
 
     /// Retrieves a type-erased reference to the stream.
@@ -91,7 +87,7 @@ pub fn wrap_windowed<'a>(
     size: u64,
 ) -> io::Result<OwningWindowedReadStream<'a>> {
     base.seek(SeekFrom::Start(offset))?;
-    io::Result::Ok(OwningWindowedReadStream { base, begin: offset, end: offset + size })
+    Ok(OwningWindowedReadStream { base, begin: offset, end: offset + size })
 }
 
 /// A non-owning window into an existing [`ReadStream`].
@@ -110,7 +106,7 @@ impl<'a> SharedWindowedReadStream<'a> {
         self.base.seek(SeekFrom::Start(begin))?;
         self.begin = begin;
         self.end = end;
-        io::Result::Ok(())
+        Ok(())
     }
 }
 
@@ -137,9 +133,9 @@ fn windowed_seek(stream: &mut dyn WindowedReadStream, pos: SeekFrom) -> io::Resu
         SeekFrom::Current(_) => pos,
     })?;
     if result < begin || result > end {
-        io::Result::Err(io::Error::from(io::ErrorKind::UnexpectedEof))
+        Err(io::Error::from(io::ErrorKind::UnexpectedEof))
     } else {
-        io::Result::Ok(result - begin)
+        Ok(result - begin)
     }
 }
 
@@ -151,12 +147,12 @@ impl<'a> Seek for OwningWindowedReadStream<'a> {
     fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> { windowed_seek(self, pos) }
 
     fn stream_position(&mut self) -> io::Result<u64> {
-        Result::Ok(self.base.stream_position()? - self.begin)
+        Ok(self.base.stream_position()? - self.begin)
     }
 }
 
 impl<'a> ReadStream for OwningWindowedReadStream<'a> {
-    fn stable_stream_len(&mut self) -> io::Result<u64> { Result::Ok(self.end - self.begin) }
+    fn stable_stream_len(&mut self) -> io::Result<u64> { Ok(self.end - self.begin) }
 
     fn as_dyn(&mut self) -> &mut dyn ReadStream { self }
 }
@@ -175,12 +171,12 @@ impl<'a> Seek for SharedWindowedReadStream<'a> {
     fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> { windowed_seek(self, pos) }
 
     fn stream_position(&mut self) -> io::Result<u64> {
-        Result::Ok(self.base.stream_position()? - self.begin)
+        Ok(self.base.stream_position()? - self.begin)
     }
 }
 
 impl<'a> ReadStream for SharedWindowedReadStream<'a> {
-    fn stable_stream_len(&mut self) -> io::Result<u64> { Result::Ok(self.end - self.begin) }
+    fn stable_stream_len(&mut self) -> io::Result<u64> { Ok(self.end - self.begin) }
 
     fn as_dyn(&mut self) -> &mut dyn ReadStream { self }
 }

src/util/lfg.rs

@@ -0,0 +1,77 @@
+use std::{cmp::min, io, io::Read};
+
+pub(crate) const LFG_K: usize = 521;
+pub(crate) const LFG_J: usize = 32;
+pub(crate) const SEED_SIZE: usize = 17;
+
+/// Lagged Fibonacci generator for Wii partition junk data.
+/// https://github.com/dolphin-emu/dolphin/blob/master/docs/WiaAndRvz.md#prng-algorithm
+pub(crate) struct LaggedFibonacci {
+    buffer: [u32; LFG_K],
+    position: usize,
+}
+
+impl Default for LaggedFibonacci {
+    fn default() -> Self { Self { buffer: [0u32; LFG_K], position: 0 } }
+}
+
+impl LaggedFibonacci {
+    fn init(&mut self) {
+        for i in SEED_SIZE..LFG_K {
+            self.buffer[i] =
+                (self.buffer[i - 17] << 23) ^ (self.buffer[i - 16] >> 9) ^ self.buffer[i - 1];
+        }
+        for x in self.buffer.iter_mut() {
+            *x = ((*x & 0xFF00FFFF) | (*x >> 2 & 0x00FF0000)).swap_bytes();
+        }
+        for _ in 0..4 {
+            self.forward();
+        }
+    }
+
+    pub(crate) fn init_with_reader<R>(&mut self, reader: &mut R) -> io::Result<()>
+    where R: Read + ?Sized {
+        reader.read_exact(bytemuck::cast_slice_mut(&mut self.buffer[..SEED_SIZE]))?;
+        for x in self.buffer[..SEED_SIZE].iter_mut() {
+            *x = u32::from_be(*x);
+        }
+        self.position = 0;
+        self.init();
+        Ok(())
+    }
+
+    pub(crate) fn forward(&mut self) {
+        for i in 0..LFG_J {
+            self.buffer[i] ^= self.buffer[i + LFG_K - LFG_J];
+        }
+        for i in LFG_J..LFG_K {
+            self.buffer[i] ^= self.buffer[i - LFG_J];
+        }
+    }
+
+    pub(crate) fn skip(&mut self, n: usize) {
+        self.position += n;
+        while self.position >= LFG_K * 4 {
+            self.forward();
+            self.position -= LFG_K * 4;
+        }
+    }
+
+    #[inline]
+    fn bytes(&self) -> &[u8; LFG_K * 4] {
+        unsafe { &*(self.buffer.as_ptr() as *const [u8; LFG_K * 4]) }
+    }
+
+    pub(crate) fn fill(&mut self, mut buf: &mut [u8]) {
+        while !buf.is_empty() {
+            let len = min(buf.len(), LFG_K * 4 - self.position);
+            buf[..len].copy_from_slice(&self.bytes()[self.position..self.position + len]);
+            self.position += len;
+            buf = &mut buf[len..];
+            if self.position == LFG_K * 4 {
+                self.forward();
+                self.position = 0;
+            }
+        }
+    }
+}

src/util/mod.rs

@@ -0,0 +1,13 @@
+use std::ops::{Div, Rem};
+
+pub(crate) mod lfg;
+pub(crate) mod reader;
+pub(crate) mod take_seek;
+
+#[inline(always)]
+pub(crate) fn div_rem<T>(x: T, y: T) -> (T, T)
+where T: Div<Output = T> + Rem<Output = T> + Copy {
+    let quot = x / y;
+    let rem = x % y;
+    (quot, rem)
+}

src/util/reader.rs

@@ -0,0 +1,243 @@
+use std::{ffi::CString, io, io::Read};
+
+use io::Write;
+
+pub(crate) const DYNAMIC_SIZE: usize = 0;
+
+pub(crate) const fn struct_size<const N: usize>(fields: [usize; N]) -> usize {
+    let mut result = 0;
+    let mut i = 0;
+    while i < N {
+        let size = fields[i];
+        if size == DYNAMIC_SIZE {
+            // Dynamically sized
+            return DYNAMIC_SIZE;
+        }
+        result += size;
+        i += 1;
+    }
+    result
+}
+
+pub(crate) fn skip_bytes<const N: usize, R>(reader: &mut R) -> io::Result<()>
+where R: Read + ?Sized {
+    let mut buf = [0u8; N];
+    reader.read_exact(&mut buf)?;
+    Ok(())
+}
+
+pub(crate) trait FromReader: Sized {
+    type Args<'a>;
+
+    const STATIC_SIZE: usize;
+
+    fn from_reader_args<R>(reader: &mut R, args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized;
+
+    fn from_reader<'a, R>(reader: &mut R) -> io::Result<Self>
+    where
+        R: Read + ?Sized,
+        Self::Args<'a>: Default,
+    {
+        Self::from_reader_args(reader, Default::default())
+    }
+}
+
+macro_rules! impl_from_reader {
+    ($($t:ty),*) => {
+        $(
+            impl FromReader for $t {
+                type Args<'a> = ();
+
+                const STATIC_SIZE: usize = std::mem::size_of::<Self>();
+
+                fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self> where R: Read + ?Sized{
+                    let mut buf = [0u8; Self::STATIC_SIZE];
+                    reader.read_exact(&mut buf)?;
+                    Ok(Self::from_be_bytes(buf))
+                }
+            }
+        )*
+    };
+}
+
+impl_from_reader!(u8, u16, u32, u64, u128, i8, i16, i32, i64, i128);
+
+#[repr(transparent)]
+pub struct U24(pub u32);
+
+impl FromReader for U24 {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = 3;
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        let mut buf = [0u8; 4];
+        reader.read_exact(&mut buf[1..])?;
+        Ok(U24(u32::from_be_bytes(buf)))
+    }
+}
+
+impl<const N: usize> FromReader for [u8; N] {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = N;
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        let mut buf = [0u8; N];
+        reader.read_exact(&mut buf)?;
+        Ok(buf)
+    }
+}
+
+impl<const N: usize> FromReader for [u32; N] {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = N * u32::STATIC_SIZE;
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        let mut buf = [0u32; N];
+        reader.read_exact(unsafe {
+            std::slice::from_raw_parts_mut(buf.as_mut_ptr() as *mut u8, Self::STATIC_SIZE)
+        })?;
+        for x in buf.iter_mut() {
+            *x = u32::from_be(*x);
+        }
+        Ok(buf)
+    }
+}
+
+impl FromReader for CString {
+    type Args<'a> = ();
+
+    const STATIC_SIZE: usize = DYNAMIC_SIZE;
+
+    fn from_reader_args<R>(reader: &mut R, _args: Self::Args<'_>) -> io::Result<Self>
+    where R: Read + ?Sized {
+        let mut buf = Vec::new();
+        loop {
+            let mut byte = [0u8; 1];
+            reader.read_exact(&mut byte)?;
+            buf.push(byte[0]);
+            if byte[0] == 0 {
+                break;
+            }
+        }
+        Ok(unsafe { CString::from_vec_with_nul_unchecked(buf) })
+    }
+}
+
+pub(crate) fn read_bytes<R>(reader: &mut R, count: usize) -> io::Result<Vec<u8>>
+where R: Read + ?Sized {
+    let mut buf = vec![0u8; count];
+    reader.read_exact(&mut buf)?;
+    Ok(buf)
+}
+
+pub(crate) fn read_vec<'a, T, R>(reader: &mut R, count: usize) -> io::Result<Vec<T>>
+where
+    T: FromReader,
+    R: Read + ?Sized,
+    <T as FromReader>::Args<'a>: Default,
+{
+    let mut vec = Vec::with_capacity(count);
+    if T::STATIC_SIZE != DYNAMIC_SIZE {
+        // Read the entire buffer at once
+        let buf = read_bytes(reader, T::STATIC_SIZE * count)?;
+        let mut slice = buf.as_slice();
+        for _ in 0..count {
+            vec.push(T::from_reader(&mut slice)?);
+        }
+    } else {
+        for _ in 0..count {
+            vec.push(T::from_reader(reader)?);
+        }
+    }
+    Ok(vec)
+}
+
+pub(crate) trait ToWriter: Sized {
+    fn to_writer<W>(&self, writer: &mut W) -> io::Result<()>
+    where W: Write + ?Sized;
+
+    fn to_bytes(&self) -> io::Result<Vec<u8>> {
+        let mut buf = vec![0u8; self.write_size()];
+        self.to_writer(&mut buf.as_mut_slice())?;
+        Ok(buf)
+    }
+
+    fn write_size(&self) -> usize;
+}
+
+macro_rules! impl_to_writer {
+    ($($t:ty),*) => {
+        $(
+            impl ToWriter for $t {
+                fn to_writer<W>(&self, writer: &mut W) -> io::Result<()>
+                where W: Write + ?Sized {
+                    writer.write_all(&self.to_be_bytes())
+                }
+
+                fn to_bytes(&self) -> io::Result<Vec<u8>> {
+                    Ok(self.to_be_bytes().to_vec())
+                }
+
+                fn write_size(&self) -> usize {
+                    std::mem::size_of::<Self>()
+                }
+            }
+        )*
+    };
+}
+
+impl_to_writer!(u8, u16, u32, u64, u128, i8, i16, i32, i64, i128);
+
+impl ToWriter for U24 {
+    fn to_writer<W>(&self, writer: &mut W) -> io::Result<()>
+    where W: Write + ?Sized {
+        writer.write_all(&self.0.to_be_bytes()[1..])
+    }
+
+    fn write_size(&self) -> usize { 3 }
+}
+
+impl<const N: usize> ToWriter for [u8; N] {
+    fn to_writer<W>(&self, writer: &mut W) -> io::Result<()>
+    where W: Write + ?Sized {
+        writer.write_all(self)
+    }
+
+    fn write_size(&self) -> usize { N }
+}
+
+impl ToWriter for &[u8] {
+    fn to_writer<W>(&self, writer: &mut W) -> io::Result<()>
+    where W: Write + ?Sized {
+        writer.write_all(self)
+    }
+
+    fn write_size(&self) -> usize { self.len() }
+}
+
+impl ToWriter for Vec<u8> {
+    fn to_writer<W>(&self, writer: &mut W) -> io::Result<()>
+    where W: Write + ?Sized {
+        writer.write_all(self)
+    }
+
+    fn write_size(&self) -> usize { self.len() }
+}
+
+pub(crate) fn write_vec<T, W>(writer: &mut W, vec: &[T]) -> io::Result<()>
+where
+    T: ToWriter,
+    W: Write + ?Sized,
+{
+    for item in vec {
+        item.to_writer(writer)?;
+    }
+    Ok(())
+}

src/util/take_seek.rs

@@ -0,0 +1,127 @@
+// From https://github.com/jam1garner/binrw/blob/e96a1320287ec83d1f471525ffa380800ec9e124/binrw/src/io/take_seek.rs
+// MIT License
+//
+// Copyright (c) jam1garner and other contributors
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+#![allow(dead_code)]
+//! Types for seekable reader adapters which limit the number of bytes read from
+//! the underlying reader.
+
+use std::io::{Read, Result, Seek, SeekFrom};
+
+/// Read adapter which limits the bytes read from an underlying reader, with
+/// seek support.
+///
+/// This struct is generally created by importing the [`TakeSeekExt`] extension
+/// and calling [`take_seek`] on a reader.
+///
+/// [`take_seek`]: TakeSeekExt::take_seek
+#[derive(Debug)]
+pub struct TakeSeek<T> {
+    inner: T,
+    pos: u64,
+    end: u64,
+}
+
+impl<T> TakeSeek<T> {
+    /// Gets a reference to the underlying reader.
+    pub fn get_ref(&self) -> &T { &self.inner }
+
+    /// Gets a mutable reference to the underlying reader.
+    ///
+    /// Care should be taken to avoid modifying the internal I/O state of the
+    /// underlying reader as doing so may corrupt the internal limit of this
+    /// `TakeSeek`.
+    pub fn get_mut(&mut self) -> &mut T { &mut self.inner }
+
+    /// Consumes this wrapper, returning the wrapped value.
+    pub fn into_inner(self) -> T { self.inner }
+
+    /// Returns the number of bytes that can be read before this instance will
+    /// return EOF.
+    ///
+    /// # Note
+    ///
+    /// This instance may reach EOF after reading fewer bytes than indicated by
+    /// this method if the underlying [`Read`] instance reaches EOF.
+    pub fn limit(&self) -> u64 { self.end.saturating_sub(self.pos) }
+}
+
+impl<T: Seek> TakeSeek<T> {
+    /// Sets the number of bytes that can be read before this instance will
+    /// return EOF. This is the same as constructing a new `TakeSeek` instance,
+    /// so the amount of bytes read and the previous limit value don’t matter
+    /// when calling this method.
+    ///
+    /// # Panics
+    ///
+    /// Panics if the inner stream returns an error from `stream_position`.
+    pub fn set_limit(&mut self, limit: u64) {
+        let pos = self.inner.stream_position().expect("cannot get position for `set_limit`");
+        self.pos = pos;
+        self.end = pos + limit;
+    }
+}
+
+impl<T: Read> Read for TakeSeek<T> {
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
+        let limit = self.limit();
+
+        // Don't call into inner reader at all at EOF because it may still block
+        if limit == 0 {
+            return Ok(0);
+        }
+
+        // Lint: It is impossible for this cast to truncate because the value
+        // being cast is the minimum of two values, and one of the value types
+        // is already `usize`.
+        #[allow(clippy::cast_possible_truncation)]
+        let max = (buf.len() as u64).min(limit) as usize;
+        let n = self.inner.read(&mut buf[0..max])?;
+        self.pos += n as u64;
+        Ok(n)
+    }
+}
+
+impl<T: Seek> Seek for TakeSeek<T> {
+    fn seek(&mut self, pos: SeekFrom) -> Result<u64> {
+        self.pos = self.inner.seek(pos)?;
+        Ok(self.pos)
+    }
+
+    fn stream_position(&mut self) -> Result<u64> { Ok(self.pos) }
+}
+
+/// An extension trait that implements `take_seek()` for compatible streams.
+pub trait TakeSeekExt {
+    /// Creates an adapter which will read at most `limit` bytes from the
+    /// wrapped stream.
+    fn take_seek(self, limit: u64) -> TakeSeek<Self>
+    where Self: Sized;
+}
+
+impl<T: Read + Seek> TakeSeekExt for T {
+    fn take_seek(mut self, limit: u64) -> TakeSeek<Self>
+    where Self: Sized {
+        let pos = self.stream_position().expect("cannot get position for `take_seek`");
+
+        TakeSeek { inner: self, pos, end: pos + limit }
+    }
+}