Media types
OSDF defines a small set of media types so that tools, gateways, and operating systems can recognize and route packages reliably.
Package types
| Extension | Media type | Description |
|---|---|---|
.osdf | application/osdf | Standard secure document package |
.osdfa | application/osdf-archive | Long-term archival profile (OSDF-A) |
.osdfx | application/osdf-capsule | Compartmentalized zero-trust capsule |
Internal object types
| Path suffix | Media type | Description |
|---|---|---|
.osdfc | application/osdf-content | Canonical semantic content |
manifest.json | application/osdf-manifest+json | Object table and digests |
signatures.json | application/osdf-signatures+json | Signature objects |
proofs.json | application/osdf-proofs+json | Transparency proofs |
Renditions
Embedded human-readable renditions keep their native media types - for example
application/pdf for a frozen PDF/A rendition, or standard image and video types
for evidence packages.
Detection
Tools should detect OSDF by the magic header first and the extension second. Never rely on the extension alone for a security decision.