Validate semantic file record invariants

2 files changed, 59 insertions, 0 deletions

diff --git a/src/manifest.rs b/src/manifest.rs
index 3a34af7..bc09073 100644
--- a/src/manifest.rs
+++ b/src/manifest.rs
@@ -31,6 +31,7 @@ impl ArtifactManifest {
         files.sort_by(|left, right| left.path.cmp(&right.path));
         services.sort_by(|left, right| left.name.cmp(&right.name));
         archive_members.sort_by(|left, right| left.path.cmp(&right.path));
+        validate_file_records(&files)?;
         ensure_unique("package", packages.iter().map(|record| record.name.as_str()))?;
         ensure_unique("file", files.iter().map(|record| record.path.as_str()))?;
         ensure_unique("service", services.iter().map(|record| record.name.as_str()))?;
@@ -355,6 +356,31 @@ fn link_target(path: &Path) -> Result<String> {
     Ok(value.to_owned())
 }
 
+fn validate_file_records(records: &[FileRecord]) -> Result<()> {
+    for record in records {
+        match record.kind.as_str() {
+            "file" => {
+                if record.digest.as_deref().is_none_or(str::is_empty) {
+                    bail!("regular file record requires a digest: {}", record.path);
+                }
+                if record.target.is_some() {
+                    bail!("regular file record cannot carry a target: {}", record.path);
+                }
+            }
+            "symlink" | "hardlink" => {
+                if record.digest.is_some() {
+                    bail!("{} record cannot carry a digest: {}", record.kind, record.path);
+                }
+                if record.target.as_deref().is_none_or(str::is_empty) {
+                    bail!("{} record requires a target: {}", record.kind, record.path);
+                }
+            }
+            _ => bail!("unsupported file record kind {}: {}", record.kind, record.path),
+        }
+    }
+    Ok(())
+}
+
 fn ensure_unique<'a>(kind: &str, keys: impl IntoIterator<Item = &'a str>) -> Result<()> {
     let mut seen = HashSet::new();
     for key in keys {
diff --git a/tests/compare.rs b/tests/compare.rs
index 43c91e0..45522d1 100644
--- a/tests/compare.rs
+++ b/tests/compare.rs
@@ -173,6 +173,39 @@ fn rejects_duplicate_semantic_keys() {
 }
 
 #[test]
+fn rejects_malformed_file_records_before_comparison() {
+    let error = ArtifactManifest::new(
+        vec![],
+        vec![FileRecord {
+            path: "etc/controller.conf".into(),
+            kind: "file".into(),
+            digest: None,
+            target: None,
+        }],
+        None,
+        vec![],
+        vec![],
+    )
+    .expect_err("regular files require a digest");
+    assert!(error.to_string().contains("regular file record requires a digest"));
+
+    let error = ArtifactManifest::new(
+        vec![],
+        vec![FileRecord {
+            path: "etc/controller-link".into(),
+            kind: "symlink".into(),
+            digest: Some("not-applicable".into()),
+            target: Some("controller.conf".into()),
+        }],
+        None,
+        vec![],
+        vec![],
+    )
+    .expect_err("symlinks cannot carry a digest");
+    assert!(error.to_string().contains("symlink record cannot carry a digest"));
+}
+
+#[test]
 fn collects_semantic_facts_from_native_rootfs_and_tar_artifact() {
     let fixture = tempdir().expect("temporary directory");
     let rootfs = fixture.path().join("rootfs");