Use fewer dependencies in Windows build script

This removes the dependencies on the platform crate as well as the
sha256 crate, opting for the sri crate instead to check file integrity.

tun/Cargo.toml

@@ -6,20 +6,19 @@ edition = "2021"
 [dependencies]
 libc = "0.2"
 fehler = "1.0"
-nix = { version = "0.25", features = ["ioctl"] }
+nix = { version = "0.26", features = ["ioctl"] }
 socket2 = "0.4"
-tokio = { version = "1.21", features = [] }
+tokio = { version = "1.28", features = [] }
 
 [target.'cfg(windows)'.dependencies]
 libloading = "0.7"
 widestring = "1.0"
+windows = { version = "0.48", features = ["Win32_Foundation", "Win32_NetworkManagement_IpHelper"] }
 
 [target.'cfg(windows)'.build-dependencies]
 anyhow = "1.0"
-bindgen = "0.61"
+bindgen = "0.65"
-hex-literal = "0.3"
-platforms = "3.0"
 reqwest = { version = "0.11", features = ["native-tls"] }
-sha2 = "0.10"
+ssri = { version = "9.0", default-features = false }
-tokio = { version = "1.21", features = ["rt"] }
+tokio = { version = "1.28", features = ["rt"] }
 zip = { version = "0.6", features = ["deflate"] }

tun/build.rs

@@ -7,10 +7,11 @@ async fn main() -> anyhow::Result<()> {
         .await?
         .bytes()
         .await?;
-    assert_content_hash(
+
-        &buf,
+    ssri::IntegrityChecker::new("sha256-B8JWGF1u42UuCfpVwLZz4mJLVl4CxLkJHHnKfS8k71E=".parse()?)
-        hex_literal::hex!("07c256185d6ee3652e09fa55c0b673e2624b565e02c4b9091c79ca7d2f24ef51"),
+        .chain(&buf)
-    );
+        .result()?;
+
     let mut archive = zip::ZipArchive::new(Cursor::new(buf))?;
 
     let out_dir = std::path::PathBuf::from(std::env::var("OUT_DIR")?);
@@ -46,13 +47,14 @@ async fn main() -> anyhow::Result<()> {
     bindings.write_to_file(out_dir.join("wintun.rs"))?;
 
     let mut library = Vec::new();
-    let platform = platforms::Platform::find(&std::env::var("TARGET")?).unwrap();
+    let target = std::env::var("TARGET")?;
-    let arch = match platform.target_arch {
+    let arch = match target.split("-").next() {
-        platforms::target::Arch::Arm => "arm",
+        Some("i686") => "x86",
-        platforms::Arch::AArch64 => "arm64",
+        Some("x86_64") => "amd64",
-        platforms::Arch::X86 => "x86",
+        Some("aarch64") => "arm64",
-        platforms::Arch::X86_64 => "amd64",
+        Some("thumbv7a") => "arm",
-        arch => panic!("{} is not a supported architecture", arch),
+        Some(a) => panic!("{} is not a supported architecture", a),
+        None => unreachable!(),
     };
     archive
         .by_name(&format!("wintun/bin/{}/wintun.dll", arch))?
@@ -68,12 +70,3 @@ async fn main() -> anyhow::Result<()> {
 fn main() {
     println!("cargo:rerun-if-changed=build.rs");
 }
-
-#[cfg(windows)]
-fn assert_content_hash(content: &[u8], hash: [u8; 32]) {
-    use sha2::digest::Update;
-    use sha2::Digest;
-
-    let computed = sha2::Sha256::new().chain(content).finalize();
-    assert_eq!(computed.as_slice(), &hash[..]);
-}

tun/src/windows/mod.rs

@@ -1,7 +1,8 @@
-use std::io::Result;
+use fehler::throws;
+use std::io::Error;
 use std::ptr;
 use widestring::{u16cstr, U16CString};
-
+use windows::Win32::Foundation::GetLastError;
 mod queue;
 
 pub use queue::TunQueue;
@@ -13,16 +14,20 @@ pub struct TunInterface {
 }
 
 impl TunInterface {
-    pub fn new() -> Result<TunInterface> {
+    #[throws]
-        let name = U16CString::from(u16cstr!("ConradNet"));
+    pub fn new() -> TunInterface {
+        let name = U16CString::from(u16cstr!("Burrow"));
         let wintun = sys::wintun::default();
         let handle =
             unsafe { wintun.WintunCreateAdapter(name.as_ptr(), name.as_ptr(), ptr::null()) };
-        Ok(TunInterface {
+        if handle.is_null() {
+            unsafe { GetLastError() }.ok()?
+        }
+        TunInterface {
             wintun,
             handle,
-            name: String::from("ConradNet"),
+            name: String::from("Burrow"),
-        })
+        }
     }
 
     pub fn name(&self) -> String {