feat(install): implicit-trust model for user-declared sources

crates/soar-config/src/packages.rs

@@ -199,6 +199,13 @@ pub struct PackageOptions {
     /// Direct URL to download the package from (makes it a "local" package).
     pub url: Option<String>,
 
+    /// Expected BLAKE3 checksum (hex) of the downloaded artifact, for `url`/`github`/
+    /// `gitlab` packages. When set, soar verifies the download against it and refuses to
+    /// install on mismatch.
+    /// Without it, these user-declared sources install on implicit trust.
+    /// Has no effect on registry packages, which already ship their own checksum.
+    pub bsum: Option<String>,
+
     /// GitHub repository in "owner/repo" format for installing from releases.
     /// When set, soar fetches the latest release and downloads the matching asset.
     pub github: Option<String>,
@@ -301,6 +308,7 @@ pub struct ResolvedPackage {
     pub version: Option<String>,
     pub repo: Option<String>,
     pub url: Option<String>,
+    pub bsum: Option<String>,
     pub github: Option<String>,
     pub gitlab: Option<String>,
     pub asset_pattern: Option<String>,
@@ -340,6 +348,7 @@ impl PackageSpec {
                     version,
                     repo: None,
                     url: None,
+                    bsum: None,
                     github: None,
                     gitlab: None,
                     asset_pattern: None,
@@ -376,6 +385,7 @@ impl PackageSpec {
                     version,
                     repo: opts.repo.clone(),
                     url: opts.url.clone(),
+                    bsum: opts.bsum.clone(),
                     github: opts.github.clone(),
                     gitlab: opts.gitlab.clone(),
                     asset_pattern: opts.asset_pattern.clone(),
@@ -663,6 +673,34 @@ special = { profile = "isolated" }
         assert_eq!(resolved[0].profile, Some("isolated".to_string()));
     }
 
+    #[test]
+    fn test_bsum_pin_resolved() {
+        let toml_str = r#"
+[packages]
+myapp = { url = "https://example.com/myapp-1.0.AppImage", bsum = "abc123" }
+nopin = { url = "https://example.com/nopin-1.0.AppImage" }
+"#;
+        let config: PackagesConfig = toml::from_str(toml_str).unwrap();
+        let resolved = config.resolved_packages();
+
+        let myapp = resolved.iter().find(|p| p.name == "myapp").unwrap();
+        let nopin = resolved.iter().find(|p| p.name == "nopin").unwrap();
+
+        assert_eq!(myapp.bsum, Some("abc123".to_string()));
+        assert_eq!(nopin.bsum, None);
+    }
+
+    #[test]
+    fn test_bsum_none_for_simple_spec() {
+        let toml_str = r#"
+[packages]
+curl = "*"
+"#;
+        let config: PackagesConfig = toml::from_str(toml_str).unwrap();
+        let resolved = config.resolved_packages();
+        assert_eq!(resolved[0].bsum, None);
+    }
+
     #[test]
     fn test_portable_config() {
         let toml_str = r#"

crates/soar-operations/src/apply.rs

@@ -636,8 +636,10 @@ fn create_url_install_target(
     resolved: &ResolvedPackage,
     existing: Option<InstalledPackage>,
 ) -> InstallTarget {
+    let mut package = url_pkg.to_package();
+    package.bsum = resolved.bsum.as_ref().map(|s| s.trim().to_lowercase());
     InstallTarget {
-        package: url_pkg.to_package(),
+        package,
         existing_install: existing,
         pinned: resolved.pinned,
         profile: resolved.profile.clone(),

crates/soar-operations/src/install.rs

@@ -690,6 +690,14 @@ pub async fn perform_installation(
     })
 }
 
+/// Whether the registry-style "checksum or signature required" integrity gate is
+/// inapplicable to this package's source.
+/// Exemption only skips the gate; an explicit `bsum` (e.g. a user-provided pin) is still
+/// enforced by checksum verification.
+fn source_skips_integrity_gate(pkg: &Package) -> bool {
+    pkg.repo_name == "local" || pkg.ghcr_pkg.is_some()
+}
+
 #[allow(clippy::too_many_arguments)]
 async fn install_single_package(
     ctx: &SoarContext,
@@ -764,7 +772,9 @@ async fn install_single_package(
     let config = ctx.config();
     let bin_dir = config.get_bin_path()?;
 
-    if !no_verify && pkg.bsum.is_none() {
+    let skip_integrity_gate = source_skips_integrity_gate(pkg);
+
+    if !no_verify && !skip_integrity_gate && pkg.bsum.is_none() {
         let has_signing = config
             .get_repository(&pkg.repo_name)
             .map(|repo| repo.signature_verification() && repo.pubkey.is_some())
@@ -919,7 +929,7 @@ async fn install_single_package(
         cleanup_sig_files(&install_dir);
     }
 
-    if !no_verify && pkg.bsum.is_none() && verified_sig_count == 0 {
+    if !no_verify && !skip_integrity_gate && pkg.bsum.is_none() && verified_sig_count == 0 {
         return Err(SoarError::Custom(format!(
             "Refusing to install {}#{}: no checksum and no valid signature found to verify integrity (use --no-verify to override)",
             pkg.pkg_name, pkg.pkg_id
@@ -1133,3 +1143,55 @@ fn cleanup_sig_files(install_dir: &Path) {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn pkg(repo_name: &str, ghcr: Option<&str>, bsum: Option<&str>) -> Package {
+        Package {
+            repo_name: repo_name.to_string(),
+            ghcr_pkg: ghcr.map(String::from),
+            bsum: bsum.map(String::from),
+            ..Default::default()
+        }
+    }
+
+    #[test]
+    fn local_source_skips_integrity_gate() {
+        assert!(source_skips_integrity_gate(&pkg("local", None, None)));
+    }
+
+    #[test]
+    fn ghcr_source_skips_integrity_gate() {
+        assert!(source_skips_integrity_gate(&pkg(
+            "local",
+            Some("ghcr.io/org/repo:tag"),
+            None
+        )));
+        assert!(source_skips_integrity_gate(&pkg(
+            "some-repo",
+            Some("ghcr.io/org/repo:tag"),
+            None
+        )));
+    }
+
+    #[test]
+    fn registry_source_is_subject_to_integrity_gate() {
+        assert!(!source_skips_integrity_gate(&pkg("soarpkgs", None, None)));
+    }
+
+    #[test]
+    fn integrity_gate_exemption_is_independent_of_pinned_bsum() {
+        assert!(source_skips_integrity_gate(&pkg(
+            "local",
+            None,
+            Some("deadbeef")
+        )));
+        assert!(!source_skips_integrity_gate(&pkg(
+            "soarpkgs",
+            None,
+            Some("deadbeef")
+        )));
+    }
+}