Make meta tool build on Linux

4 files changed, 39 insertions, 33 deletions

diff --git a/mullvad-update/src/client/app.rs b/mullvad-update/src/client/app.rs
index decf8d932b..6b894dd201 100644
--- a/mullvad-update/src/client/app.rs
+++ b/mullvad-update/src/client/app.rs
@@ -1,3 +1,5 @@
+#![cfg(any(target_os = "macos", target_os = "windows"))]
+
 //! This module implements the flow of downloading and verifying the app.
 
 use std::{ffi::OsString, path::PathBuf, time::Duration};
diff --git a/mullvad-update/src/client/verify.rs b/mullvad-update/src/client/verify.rs
index 08738206ee..28a53f839d 100644
--- a/mullvad-update/src/client/verify.rs
+++ b/mullvad-update/src/client/verify.rs
@@ -1,8 +1,7 @@
 use anyhow::Context;
-use sha2::Digest;
 use tokio::{
     fs,
-    io::{AsyncRead, AsyncReadExt, BufReader},
+    io::{AsyncRead, BufReader},
 };
 
 use std::{future::Future, path::Path};
@@ -22,11 +21,6 @@ pub trait AppVerifier: 'static + Clone {
 #[derive(Clone)]
 pub struct Sha256Verifier;
 
-impl Sha256Verifier {
-    /// Maximum number of bytes to read at a time
-    const BUF_SIZE: usize = 1024 * 1024;
-}
-
 impl AppVerifier for Sha256Verifier {
     /// The checksum
     type Parameters = [u8; 32];
@@ -49,34 +43,11 @@ impl AppVerifier for Sha256Verifier {
 }
 
 impl Sha256Verifier {
-    pub async fn generate_hash(
-        mut reader: impl AsyncRead + Unpin,
-    ) -> anyhow::Result<[u8; 32]>
-    {
-        let mut hasher = sha2::Sha256::new();
-
-        // Read data into hasher
-        let mut buffer = vec![0u8; Self::BUF_SIZE];
-        loop {
-            let read_n = reader
-                .read(&mut buffer)
-                .await
-                .context("Error reading bin file")?;
-            if read_n == 0 {
-                // We're done
-                break;
-            }
-            hasher.update(&buffer[..read_n]);
-        }
-
-        Ok(hasher.finalize().into())
-    }
-
     async fn verify_inner(
         reader: impl AsyncRead + Unpin,
         expected_hash: [u8; 32],
     ) -> anyhow::Result<()> {
-        let actual_hash = Self::generate_hash(reader).await?;
+        let actual_hash = crate::hash::checksum(reader).await?;
 
         // Verify that hash is correct
         if expected_hash != actual_hash {
@@ -90,6 +61,7 @@ impl Sha256Verifier {
 #[cfg(test)]
 mod test {
     use rand::RngCore;
+    use sha2::Digest;
     use std::io::Cursor;
 
     use super::*;
diff --git a/mullvad-update/src/hash.rs b/mullvad-update/src/hash.rs
new file mode 100644
index 0000000000..4a5891124e
--- /dev/null
+++ b/mullvad-update/src/hash.rs
@@ -0,0 +1,29 @@
+//! Compute checksum for SHA-256
+
+use anyhow::Context;
+use sha2::Digest;
+use tokio::io::{AsyncRead, AsyncReadExt};
+
+/// Maximum number of bytes to read at a time
+const BUF_SIZE: usize = 10 * 1024 * 1024;
+
+/// Generate SHA256 checksum for `reader`
+pub async fn checksum(mut reader: impl AsyncRead + Unpin) -> anyhow::Result<[u8; 32]> {
+    let mut hasher = sha2::Sha256::new();
+
+    // Read data into hasher
+    let mut buffer = vec![0u8; BUF_SIZE];
+    loop {
+        let read_n = reader
+            .read(&mut buffer)
+            .await
+            .context("Error reading bin file")?;
+        if read_n == 0 {
+            // We're done
+            break;
+        }
+        hasher.update(&buffer[..read_n]);
+    }
+
+    Ok(hasher.finalize().into())
+}
diff --git a/mullvad-update/src/lib.rs b/mullvad-update/src/lib.rs
index 2c78908089..4efd060b4b 100644
--- a/mullvad-update/src/lib.rs
+++ b/mullvad-update/src/lib.rs
@@ -1,12 +1,15 @@
 //! Support functions for securely installing or updating Mullvad VPN
 
-#[cfg(all(feature = "client", any(target_os = "windows", target_os = "macos")))]
+#[cfg(feature = "client")]
 mod client;
 
-#[cfg(all(feature = "client", any(target_os = "windows", target_os = "macos")))]
+#[cfg(feature = "client")]
 pub use client::*;
 
 pub mod version;
 
 /// Parser and serializer for version metadata
 pub mod format;
+
+#[cfg(feature = "client")]
+pub mod hash;