verify/models: enforce bundle media type

Signed-off-by: William Woodruff <[email protected]>
sigstore · Jul 12, 2023 · daaeb4f · daaeb4f
1 parent 145a6b0
commit daaeb4f
Showing 1 changed file with 8 additions and 0 deletions.
diff --git a/sigstore/verify/models.py b/sigstore/verify/models.py
@@ -48,6 +48,11 @@
 
 logger = logging.getLogger(__name__)
 
+_KNOWN_BUNDLE_TYPES: set[str] = {
+    "application/vnd.dev.sigstore.bundle+json;version=0.1",
+    "application/vnd.dev.sigstore.bundle+json;version=0.2",
+}
+
 
 class VerificationResult(BaseModel):
     """
@@ -242,6 +247,9 @@ def from_bundle(
 
         Effect: `input_` is consumed as part of construction.
         """
+        if bundle.media_type not in _KNOWN_BUNDLE_TYPES:
+            raise InvalidMaterials(f"unsupported bundle format: {bundle.media_type}")
+
         certs = bundle.verification_material.x509_certificate_chain.certificates
 
         if len(certs) == 0: