feat: store target env var at build time to help with plugin arch res…

…olution

hipcheck/build.rs

@@ -5,8 +5,18 @@ use pathbuf::pathbuf;
 use tonic_build::compile_protos;
 
 fn main() -> Result<()> {
+	// Compile the Hipcheck gRPC protocol spec to an .rs file
 	let root = env!("CARGO_MANIFEST_DIR");
 	let path = pathbuf![root, "proto", "hipcheck", "v1", "hipcheck.proto"];
 	compile_protos(path)?;
+
+	// Make the target available as a compile-time env var for plugin arch
+	// resolution
+	println!(
+		"cargo:rustc-env=TARGET={}",
+		std::env::var("TARGET").unwrap()
+	);
+	println!("cargo:rerun-if-changed-env=TARGET");
+
 	Ok(())
 }

hipcheck/src/engine.rs

@@ -5,8 +5,8 @@ use crate::{
 	cache::plugin::HcPluginCache,
 	hc_error,
 	plugin::{
-		get_plugin_key, retrieve_plugins, try_get_current_arch, Plugin, PluginManifest,
-		PluginResponse, QueryResult,
+		get_current_arch, get_plugin_key, retrieve_plugins, Plugin, PluginManifest, PluginResponse,
+		QueryResult,
 	},
 	policy::PolicyFile,
 	util::fs::{find_file_by_name, read_string},
@@ -230,7 +230,7 @@ pub fn start_plugins(
 		/* jitter_percent */ 10,
 	)?;
 
-	let current_arch = try_get_current_arch()?;
+	let current_arch = get_current_arch();
 	println!("CURRENT ARCH: {}", current_arch);
 
 	// retrieve, verify and extract all required plugins

hipcheck/src/plugin/arch.rs

@@ -28,6 +28,8 @@ pub enum Arch {
 	Unknown(String),
 }
 
+pub const DETECTED_ARCH_STR: &str = env!("TARGET");
+
 pub const DETECTED_ARCH: Option<KnownArch> = {
 	if cfg!(target_arch = "x86_64") {
 		if cfg!(target_os = "macos") {
@@ -57,23 +59,13 @@ pub static USER_PROVIDED_ARCH: OnceLock<Arch> = OnceLock::new();
 /// Get the target architecture for plugins. If the user provided a target,
 /// return that. Otherwise, if the `hc` binary was compiled for a supported
 /// architecture, return that. Otherwise return None.
-pub fn get_current_arch() -> Option<Arch> {
+pub fn get_current_arch() -> Arch {
 	if let Some(arch) = USER_PROVIDED_ARCH.get() {
-		Some(arch.clone())
+		arch.clone()
 	} else if let Some(known_arch) = DETECTED_ARCH {
-		Some(Arch::Known(known_arch))
-	} else {
-		None
-	}
-}
-
-/// Like `get_current_arch()`, but returns an error message suggesting the
-/// user specifies a target on the CLI
-pub fn try_get_current_arch() -> Result<Arch> {
-	if let Some(arch) = get_current_arch() {
-		Ok(arch)
+		Arch::Known(known_arch)
 	} else {
-		Err(hc_error!("Could not resolve the current machine to one of the Hipcheck known architectures. Please specify --arch on the commandline."))
+		Arch::Unknown(DETECTED_ARCH_STR.to_owned())
 	}
 }
 

hipcheck/src/plugin/download_manifest.rs

@@ -6,9 +6,9 @@ use crate::{
 	error::Error,
 	hc_error,
 	plugin::{
+		arch::Arch,
+		get_current_arch,
 		retrieval::{download_plugin, extract_plugin},
-		arch::KnownArch,
-		try_get_current_arch,
 	},
 	util::kdl::{extract_data, ParseKdlNode},
 	util::{
@@ -21,6 +21,9 @@ use kdl::{KdlDocument, KdlNode, KdlValue};
 use std::{collections::HashSet, fmt::Display, io::Read, str::FromStr};
 use url::Url;
 
+#[cfg(test)]
+use crate::plugin::arch::KnownArch;
+
 // NOTE: the implementation in this crate was largely derived from RFD #0004
 
 impl ParseKdlNode for url::Url {
@@ -225,7 +228,7 @@ pub struct DownloadManifestEntry {
 	/// but only a specific concrete version
 	pub version: PluginVersion,
 	/// The target architecture for a plugin
-	pub arch: KnownArch,
+	pub arch: Arch,
 	/// The URL of the archive file to download containing the plugin executable artifact and
 	/// plugin manifest.
 	pub url: url::Url,
@@ -251,7 +254,7 @@ impl ParseKdlNode for DownloadManifestEntry {
 		// Per RFD #0004, version is of type String
 		let version = PluginVersion(node.get("version")?.value().as_string()?.to_string());
 		// Per RFD #0004, arch is of type String
-		let arch = KnownArch::from_str(node.get("arch")?.value().as_string()?).ok()?;
+		let arch = Arch::from_str(node.get("arch")?.value().as_string()?).ok()?;
 
 		// there should be one child for each plugin and it should contain the url, hash, compress
 		// and size information
@@ -288,7 +291,7 @@ impl DownloadManifestEntry {
 		version: &PluginVersion,
 		downloaded_plugins: &'a mut HashSet<PluginId>,
 	) -> Result<&'a HashSet<PluginId>, Error> {
-		let current_arch = try_get_current_arch()?;
+		let current_arch = get_current_arch();
 
 		let plugin_id = PluginId::new(publisher.clone(), name.clone(), version.clone());
 
@@ -564,7 +567,7 @@ mod test {
 
 		let expected_entry = DownloadManifestEntry {
 			version: PluginVersion(version.to_string()),
-			arch: KnownArch::from_str(arch).unwrap(),
+			arch: Arch::Known(KnownArch::from_str(arch).unwrap()),
 			url: Url::parse(url).unwrap(),
 			hash: HashWithDigest::new(
 				HashAlgorithm::try_from(hash_alg).unwrap(),
@@ -605,7 +608,7 @@ plugin version="0.1.0" arch="x86_64-apple-darwin" {
 		assert_eq!(
 			&DownloadManifestEntry {
 				version: PluginVersion("0.1.0".to_owned()),
-				arch: KnownArch::Aarch64AppleDarwin,
+				arch: Arch::Known(KnownArch::Aarch64AppleDarwin),
 				url: Url::parse("https://github.com/mitre/hipcheck/releases/download/hipcheck-v3.4.0/hipcheck-aarch64-apple-darwin.tar.xz").unwrap(),
 				hash: HashWithDigest::new(HashAlgorithm::Sha256, "b8e111e7817c4a1eb40ed50712d04e15b369546c4748be1aa8893b553f4e756b".to_owned()),
 				compress: Compress::new(ArchiveFormat::TarXz),
@@ -618,7 +621,7 @@ plugin version="0.1.0" arch="x86_64-apple-darwin" {
 		assert_eq!(
 			&DownloadManifestEntry {
 				version: PluginVersion("0.1.0".to_owned()),
-				arch: KnownArch::X86_64AppleDarwin,
+				arch: Arch::Known(KnownArch::X86_64AppleDarwin),
 				url: Url::parse("https://github.com/mitre/hipcheck/releases/download/hipcheck-v3.4.0/hipcheck-x86_64-apple-darwin.tar.xz").unwrap(),
 				hash: HashWithDigest::new(HashAlgorithm::Sha256, "ddb8c6d26dd9a91e11c99b3bd7ee2b9585aedac6e6df614190f1ba2bfe86dc19".to_owned()),
                 compress: Compress::new(ArchiveFormat::TarXz),

hipcheck/src/plugin/mod.rs

@@ -1,21 +1,21 @@
 // SPDX-License-Identifier: Apache-2.0
 
+mod arch;
 mod download_manifest;
 mod manager;
 mod plugin_id;
 mod plugin_manifest;
 mod retrieval;
-mod arch;
 mod types;
 
 use crate::error::Result;
 pub use crate::plugin::{get_plugin_key, manager::*, plugin_id::PluginId, types::*};
+pub use arch::{get_current_arch, try_set_arch, Arch};
 pub use download_manifest::{ArchiveFormat, DownloadManifest, HashAlgorithm, HashWithDigest};
 pub use plugin_manifest::{PluginManifest, PluginName, PluginPublisher, PluginVersion};
 pub use retrieval::retrieve_plugins;
 use serde_json::Value;
 use std::collections::HashMap;
-pub use arch::{try_get_current_arch, try_set_arch, Arch};
 use tokio::sync::Mutex;
 
 pub async fn initialize_plugins(