From ad22ba9b1a7be31a903516f622b4052c766b56cd Mon Sep 17 00:00:00 2001
From: Truman Kilen <t@kilen.me>
Date: Thu, 13 Apr 2023 02:01:19 -0500
Subject: [PATCH] Obtain oodle DLL automatically

---
 Cargo.toml           |  1 +
 repak/Cargo.toml     |  4 ++++
 repak/src/entry.rs   | 41 ++++++++++++++++++++++++++++++++++++++---
 repak/src/error.rs   | 12 +++++++++---
 repak_cli/Cargo.toml |  2 +-
 5 files changed, 53 insertions(+), 7 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 5871492..242f984 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,6 +11,7 @@ edition = "2021"
 [workspace.dependencies]
 aes = "0.8.2"
 base64 = "0.21.0"
+hex = "0.4.3"
 strum = { version = "0.24", features = ["derive"] }
 
 # generated by 'cargo dist init'
diff --git a/repak/Cargo.toml b/repak/Cargo.toml
index 0a0f371..f4c2cf6 100644
--- a/repak/Cargo.toml
+++ b/repak/Cargo.toml
@@ -14,6 +14,10 @@ thiserror = "1.0"
 sha1 = "0.10.5"
 strum = { workspace = true }
 libloading = "0.7.4"
+ureq = "2.6.2"
+hex-literal = "0.4.1"
+hex = { workspace = true }
+once_cell = "1.17.1"
 
 [dev-dependencies]
 base64 = { workspace = true }
diff --git a/repak/src/entry.rs b/repak/src/entry.rs
index 95e2d28..97d7c8a 100644
--- a/repak/src/entry.rs
+++ b/repak/src/entry.rs
@@ -364,12 +364,15 @@ impl Entry {
             Some(Compression::Gzip) => decompress!(flate2::read::GzDecoder<&[u8]>),
             Some(Compression::Oodle) => {
                 #[cfg(not(target_os = "windows"))]
-                return Err(super::Error::Oodle());
+                return Err(super::Error::Oodle);
 
                 #[cfg(target_os = "windows")]
                 unsafe {
-                    let lib = libloading::Library::new("oo2core_9_win64.dll")
-                        .map_err(|_| super::Error::OodleMissing())?;
+                    use std::ops::Deref;
+                    let lib = match OODLE.deref() {
+                        Ok(lib) => Ok(lib),
+                        Err(e) => Err(super::Error::Other(e.to_string())),
+                    }?;
 
                     /*
                     let set_printf: libloading::Symbol<
@@ -459,6 +462,38 @@ impl Entry {
     }
 }
 
+use once_cell::sync::Lazy;
+static OODLE: Lazy<Result<libloading::Library, String>> =
+    Lazy::new(|| get_oodle().map_err(|e| e.to_string()));
+static OODLE_HASH: [u8; 20] = hex_literal::hex!("4bcc73614cb8fd2b0bce8d0f91ee5f3202d9d624");
+
+fn get_oodle() -> Result<libloading::Library, super::Error> {
+    use sha1::{Digest, Sha1};
+
+    let oodle = std::env::current_exe()?.with_file_name("oo2core_9_win64.dll");
+    if !oodle.exists() {
+        let mut data = vec![];
+        ureq::get("https://cdn.discordapp.com/attachments/817251677086285848/992648087371792404/oo2core_9_win64.dll")
+            .call().map_err(Box::new)?
+            .into_reader().read_to_end(&mut data)?;
+
+        std::fs::write(&oodle, data)?;
+    }
+
+    let mut hasher = Sha1::new();
+    hasher.update(std::fs::read(&oodle)?);
+    let hash = hasher.finalize();
+    (hash[..] == OODLE_HASH).then_some(()).ok_or_else(|| {
+        super::Error::Other(format!(
+            "oodle hash mismatch expected: {} got: {} ",
+            hex::encode(OODLE_HASH),
+            hex::encode(hash)
+        ))
+    })?;
+
+    unsafe { libloading::Library::new(oodle) }.map_err(|_| super::Error::OodleFailed)
+}
+
 mod test {
     #[test]
     fn test_entry() {
diff --git a/repak/src/error.rs b/repak/src/error.rs
index d5ea333..a669106 100644
--- a/repak/src/error.rs
+++ b/repak/src/error.rs
@@ -19,6 +19,9 @@ pub enum Error {
     #[error("utf16 conversion: {0}")]
     Utf16(#[from] std::string::FromUtf16Error),
 
+    #[error("ureq error: {0}")]
+    Ureq(#[from] Box<ureq::Error>), // boxed because ureq::Error is quite large
+
     #[error("bufwriter dereference: {0}")]
     IntoInner(#[from] std::io::IntoInnerError<std::io::BufWriter<Vec<u8>>>),
 
@@ -30,10 +33,10 @@ pub enum Error {
     Magic(u32),
 
     #[error("Oodle compression only supported on Windows (or WINE)")]
-    Oodle(),
+    Oodle,
 
-    #[error("Could not find oo2core_9_win64.dll for Oodle compression")]
-    OodleMissing(),
+    #[error("Could not load oo2core_9_win64.dll")]
+    OodleFailed,
 
     #[error("No entry found at {0}")]
     MissingEntry(String),
@@ -67,6 +70,9 @@ pub enum Error {
 
     #[error("version unsupported or is encrypted (possibly missing --aes-key?)")]
     UnsuportedOrEncrypted,
+
+    #[error("{0}")]
+    Other(String),
 }
 
 impl std::fmt::Debug for Error {
diff --git a/repak_cli/Cargo.toml b/repak_cli/Cargo.toml
index f42f348..9fc13c7 100644
--- a/repak_cli/Cargo.toml
+++ b/repak_cli/Cargo.toml
@@ -14,7 +14,7 @@ path = "src/main.rs"
 aes = { workspace = true }
 base64 = { workspace = true }
 clap = { version = "4.1.4", features = ["derive"] }
-hex = "0.4.3"
+hex = { workspace = true }
 indicatif = { version = "0.17.3", features = ["rayon"] }
 path-clean = "0.1.0"
 path-slash = "0.2.1"